MariaDB Connector/C is used to connect applications developed in C/C++ to MariaDB and MySQL databases.The client library is LGPL licensed.

Integration with MariaDB Server

MariaDB Connector/C is distributed with MariaDB Server packages. Eventually, it will completely replace the functionality that has traditionally been performed by libmysqlclient in those packages. Currently, MariaDB Connector/C has replaced libmysqlclient as the client library for client utilities that are distributed with MariaDB Server. See MDEV-9055 for more information.

Installing MariaDB Connector/C

MariaDB Connector/C packages can be downloaded by selecting your desired version from the following page:

• MariaDB Connector/C packages can also be downloaded by selecting C/C++ connector as the Product on the following page:

• #connectors

See the instructions below for information on how to install the MariaDB Connector/C package for your operating system.

Installing MariaDB Connector/C on Windows

To install MariaDB Connector/C on Windows, we distribute MSI packages. The MSI installation process is fairly straightforward. Both 32-bit and 64-bit MSI packages are available.

Installing MariaDB Connector/C on Linux

MariaDB Connector/C is distributed in binary tarballs on Linux.

Installing with a Package Manager

Since MariaDB Connector/C is now integrated with MariaDB Server, it can also be installed via a package manager on Linux. In order to do so, your system needs to be configured to install from one of the MariaDB repositories. The repository needs to be configured for MariaDB 10.2 or later.

You can configure your package manager to install it from MariaDB Corporation's MariaDB Package Repository by using the MariaDB Package Repository setup script.

You can also configure your package manager to install it from MariaDB Foundation's MariaDB Repository by using the MariaDB Repository Configuration Tool.

Installing with yum/dnf

On RHEL, CentOS, Fedora, and other similar Linux distributions, it is highly recommended to install the relevant RPM package from MariaDB's repository using yum or dnf. Starting with RHEL 8 and Fedora 22, yum has been replaced by dnf, which is the next major version of yum. However, yum commands still work on many systems that use dnf. For example:

sudo yum install MariaDB-shared

If you want to build applications with MariaDB Connector/C, then you will also need to install the development package. For example:

sudo yum install MariaDB-devel

Installing with apt-get

On Debian, Ubuntu, and other similar Linux distributions, it is highly recommended to install the relevant DEB package from MariaDB's repository using apt-get. For example:

sudo apt-get install libmariadb3

If you want to build applications with MariaDB Connector/C, then you will also need to install the development package. For example:

sudo apt-get install libmariadb-dev

Installing with zypper

On SLES, OpenSUSE, and other similar Linux distributions, it is highly recommended to install the relevant RPM package from MariaDB's repository using zypper. For example:

sudo zypper install MariaDB-shared

If you want to build applications with MariaDB Connector/C, then you will also need to install the development package. For example:

sudo zypper install MariaDB-devel

Installing MariaDB Connector/C from Source

See Building Connector/C From Source for information on how to build MariaDB Connector/C from source.

API - Function Reference

MariaDB Connector/C has exactly the same API as the MySQL Connector/C for MySQL 5.5

The function reference is available at:

• MariaDB Client Library for C API Functions

• MariaDB Client Library for C API Prepared Statement Functions

It is also downloadable in html format from mariadb-client-doc.zip

Configuring MariaDB Connector/C with Option Files

Just like MariaDB Server and libmysqlclient, MariaDB Connector/C can also read configuration options from client option groups in option files.

See Configuring MariaDB Connector/C with Option Files for more information.

Known Bugs and Limitations

• double to string conversion for prepared statements doesn't work correctly

• Connector 3.0.7 and below doesn't support the MySQL 8.0 default authentication protocol, caching_sha2_password. This protocol should be supported in Connector/C 3.0.8 and above.

Reporting Bugs

If you find a bug, please report it via the CONC project on MariaDB's Jira bug tracker.

Source Code

The source code is available at the mariadb-connector-c repository on GitHub.

License

GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

For licensing questions, see the Licensing FAQ.

MariaDB Connector/C supports several Linux distributions and Microsoft Windows.

Configure Package Repository (Linux)

To install MariaDB Connector/C on Linux using APT, YUM, or ZYpp, you must configure your system to use either the ES Package Repository or the CS Package Repository.

If your system is already configured to use one of these package repositories, you can skip to install MariaDB Connector/C.

Choose a package repository to configure:

ES Package Repository

MariaDB Connector/C is available from the same package repository as MariaDB Enterprise Server.

To configure the ES package repository:

1. Install curl.

   Install via APT on Debian, Ubuntu:

   Copy

   sudo apt install curl

   Install via YUM on CentOS, RHEL, Rocky Linux:

   Copy

   sudo yum install curl

   Install via ZYpp on SLES:

   Copy

   sudo zypper install curl

2. Download the mariadb_es_repo_setup utility, validate its checksum, and ensure that its permissions allow it to be executed:

   Copy

   $ curl -LsSO https://dlm.mariadb.com/enterprise-release-helpers/mariadb_es_repo_setup

   Copy

   $ echo "${checksum}  mariadb_es_repo_setup" \
       | sha256sum -c -

   Copy

   $ chmod +x mariadb_es_repo_setup

   1. Checksums of the various releases of the script can be found in the Versions section at the bottom of the MariaDB Package Repository Setup and Usage page. Subsitute ${checksum} in the example above with the latest checksum.

3. Retrieve your Customer Download Token at Customer Download Token at the MariaDB Customer Portal and substitute your token for CUSTOMER_DOWNLOAD_TOKEN in the following step.

4. Configure the ES package repository using the mariadb_es_repo_setup utility:

   Copy

   sudo ./mariadb_es_repo_setup --token="CUSTOMER_DOWNLOAD_TOKEN" --apply \
      --mariadb-server-version="10.6"

   • All major releases of ES contain the same version of MariaDB Connector/C.

   • By default, the mariadb_es_repo_setup utility will configure your system to use the package repository for ES 10.6.

   • To configure your system to use the ES package repository for a specific major release, use the --mariadb-server-version option.

5. Install MariaDB Connector/C using the package repository.

CS Package Repository

MariaDB Connector/C is available from the same package repository as MariaDB Community Server.

To configure the CS package repository:

1. Install curl.

   Install via APT on Debian, Ubuntu:

   Copy

   $ sudo apt install curl

   Install via YUM on CentOS, RHEL, Rocky Linux:

   Copy

   $ sudo yum install curl

   Install via ZYpp on SLES:

   Copy

   $ sudo zypper install curl

2. Download the mariadb_repo_setup utility, validate its checksum, and ensure that its permissions allow it to be executed:

   Copy

   curl -LsSO https://r.mariadb.com/downloads/mariadb_repo_setup

   Copy

   echo "${checksum} mariadb_repo_setup" \
       | sha256sum -c -

   Copy

   chmod +x mariadb_repo_setup

   1. Checksums of the various releases of the script can be found in the Versions section at the bottom of the MariaDB Package Repository Setup and Usage page. Subsitute ${checksum} in the example above with the latest checksum.

3. Configure the CS package repository using the mariadb_repo_setup utility:

   Copy

   sudo ./mariadb_repo_setup \
      --mariadb-server-version="mariadb-10.6"

   • All major releases of CS contain the same version of MariaDB Connector/C.

   • By default, the mariadb_repo_setup utility will configure your system to use the package repository for CS 10.6.

   • To configure your system to use the CS package repository for a specific major release, use the --mariadb-server-version option.

4. Install MariaDB Connector/C using the package repository.

Installation

Installation via Package Repository (Linux)

On supported Linux distributions, MariaDB Connector/C can be installed using APT, YUM, or ZYpp if the system is configured to use the ES Package Repository or the CS Package Repository.

Install on CentOS, RHEL, Rocky Linux

To install MariaDB Connector/C on CentOS, RHEL, and Rocky Linux, you can use YUM if you have the ES Package Repository or CS Package Repository configured.

Install MariaDB Connector/C and package dependencies:

sudo yum install MariaDB-shared MariaDB-devel

Install on Debian, Ubuntu

To install MariaDB Connector/C on Debian and Ubuntu, you can use APT if you have the ES Package Repository or CS Package Repository configured.

Install MariaDB Connector/C and package dependencies:

sudo apt install libmariadb3 libmariadb-dev

Install on SLES

To install MariaDB Connector/C on SLES, you can use ZYpp if you have the ES Package Repository or CS Package Repository configured.

Install MariaDB Connector/C and package dependencies:

sudo zypper install MariaDB-shared MariaDB-devel

Install via Binary Tarball (Linux)

MariaDB Connector/C can be installed on supported Linux distributions via a binary tarball package:

1. Go to the MariaDB Connector/C download page

2. Ensure the "Product" dropdown reads "C connector."

3. In the "Version" dropdown, select the version you want to download.

4. In the "OS" dropdown, select your Linux distribution.

5. Click on the "Download" button to download the binary tarball package.

Install via MSI (Windows)

MariaDB Connector/C can be installed on Microsoft Windows via an MSI package:

1. Go to the MariaDB Connector/C download page

2. Ensure the "Product" dropdown reads "C connector."

3. In the "Version" dropdown, select the version you want to download.

4. In the "OS" dropdown, select either "MS Windows (64-bit)" or "MS Windows (32-bit)", depending on whether you need a 64-bit or 32-bit connector.

5. Click on the "Download" button to download the MSI package.

6. When the MSI package finishes downloading, run it and follow the on-screen instructions.

_{This page is: Copyright © 2025 MariaDB. All rights reserved.}

Download MariaDB Connector/C

<< back to About MariaDB Connector/C

_{This page is: Copyright © 2025 MariaDB. All rights reserved.}

Just like MariaDB Server and libmysqlclient, MariaDB Connector/C can also read configuration options from client option groups in option files.

Default Option File Locations

MariaDB Connector/C reads option files from many different directories by default. See the sections below to find out which directories are checked for which system.

MariaDB Connector/C allows application developers to read options from the default option files by calling the mysql_optionsv function and providing the MYSQL_READ_DEFAULT_FILE option name and a NULL pointer as arguments. For example:

mysql_optionsv(mysql, MYSQL_READ_DEFAULT_FILE, NULL);

Default Option File Locations on Linux, Unix, Mac

On Linux, Unix, or Mac OS X, the default option file is called my.cnf. MariaDB Connector/C looks for the MariaDB option file in the locations and orders listed below.

The locations are dependent on whether the DEFAULT_SYSCONFDIR cmake option was defined when MariaDB Connector/C was built. This option is usually defined as /etc when building RPM packages, but it is usually not defined when building DEB packages or binary tarballs.

• When the DEFAULT_SYSCONFDIR cmake option was not defined, MariaDB Connector/C looks for the MariaDB option file in the following locations in the following order:

• When the DEFAULT_SYSCONFDIR cmake option was defined, MariaDB Connector/C looks for the MariaDB option file in the following locations in the following order:

Default Option File Locations on Windows

On Windows, the default option file can be called either my.ini or my.cnf. MariaDB Connector/C looks for the MariaDB option file in the following locations in the following order:

• The System Windows Directory is the directory returned by the GetSystemWindowsDirectory function. The value is usually C:\Windows. To find its specific value on your system, open cmd.exe and execute:

echo %WINDIR%

• The Windows Directory is the directory returned by the GetWindowsDirectory function. The value may be a private Windows Directory for the application, or it may be the same as the System Windows Directory returned by the GetSystemWindowsDirectory function.

• EXEDIR is the parent directory of the executable program that MariaDB Connector/C is linked with.

• MYSQL_HOME is the environment variable containing the path to the directory holding the server-specific my.cnf file.

Default Option File Hierarchy

MariaDB Connector/C will look in all of the above locations, in order, even if has already found an option file, and it's possible for more than one option file to exist. For example, you could have an option file in /etc/my.cnf with global settings for all servers, and then you could another option file in ~/.my.cnf (i.e.your user account's home directory) which will specify additional settings (or override previously specified setting) that are specific only to that user.

Custom Option File Locations

MariaDB Connector/C allows application developers to read option files from a custom option file by calling the mysql_optionsv function and providing the MYSQL_READ_DEFAULT_FILE option name and an option file path as arguments. For example:

mysql_optionsv(mysql, MYSQL_READ_DEFAULT_FILE, (void *)"./my_conf.cnf");

Many MariaDB clients can be configured to read options from custom options files with the following command-line arguments. They must be given as the first argument on the command-line. Application developers who use MariaDB Connector/C in their application and rely on option files may also want to consider implementing these command-line arguments:

The --defaults-file command-line option is roughly equivalent to setting the MYSQL_READ_DEFAULT_FILE option with a non-NULL argument.

The --defaults-extra-file command-line option does not yet have an equivalent option in MariaDB Connector/C. See CONC-399 for more information.

Option File Syntax

The syntax of the MariaDB option files are:

• Lines starting with

are comments.

• Empty lines are ignored.

• Option groups use the syntax [group-name]. See the Option Groups section below for more information on available option groups.

• The same option group can appear multiple times.

• The !include directive can be used to include other option files. See the Including Option Files section below for more information on this syntax.

• Unlike with the server, the !includedir directive does not include all .cnf files (and potentially .ini files) in a given directory. Instead, it reads the my.cnf and (potentially the my.ini) in the given directory. See CONC-396 for more information. See the Including Option File Directories section below for more information on this syntax.

• Dashes (-) and underscores (_) in options are interchangeable in MariaDB Connector C 3.1.1 and later. In versions before that, options must be specified exactly as they are defined. See CONC-395 for more information.

• MariaDB Connector/C does not support the option prefixes that are supported by MariaDB Server. See CONC-415 for more information.

• See the Options section below for information about available options.

Option Groups

MariaDB Connector/C reads client options from the following option groups in option files:

MariaDB Connector/C allows application developers to read options from these option groups by calling the mysql_optionsv function and providing the MYSQL_READ_DEFAULT_GROUP option name and a NULL pointer as arguments. For example:

mysql_optionsv(mysql, MYSQL_READ_DEFAULT_GROUP, NULL);

Custom Option Groups

MariaDB Connector/C allows application developers to read options from a custom option group by calling the mysql_optionsv function and providing the MYSQL_READ_DEFAULT_GROUP option name and the name of the custom option group as arguments. For example:

mysql_optionsv(mysql, MYSQL_READ_DEFAULT_GROUP, (void *)"my_section");

The custom option group will be read in addition to the default option groups listed above.

Many MariaDB clients can be configured to read options from option groups with a custom suffix by providing the following command-line argument. It must be given as the first argument on the command-line. Application developers who use MariaDB Connector/C in their application and rely on option files may also want to consider implementing this command-line argument:

The --defaults-group-suffix command-line option does not yet have an equivalent option in MariaDB Connector/C. See CONC-404 for more information.

Including Option Files

It is possible to include additional option files from another option file. For example, to include /etc/mysql/dbserver1.cnf, an option file could contain:

[client-mariadb]
...
!include /etc/mysql/dbserver1.cnf

Including Option File Directories

It is also possible to include the default option files in a directory from another option file. For example, to include the default option files in /etc/my.cnf.d/, an option file could contain:

[client-mariadb]
...
!includedir /etc/my.cnf.d/

Unlike with MariaDB server, this directive does not configure MariaDB Connector/C to include all option files ending in .cnf on Unix-like operating systems or all option files ending in .cnf and .ini files on Windows. Instead, it just configures MariaDB Connector/C to include the my.cnf in the given directory, and also the my.ini in the given directory if it's Windows. See CONC-396 for more information.

Checking Program Options

For many MariaDB clients, you can check which options a given program is going to use by using the --print-defaults command-line argument:

It must be given as the first argument on the command-line. Application developers who use MariaDB Connector/C in their application and rely on option files may also want to consider implementing this command-line argument. For example:

mysqldump --print-defaults
mysqldump would have been started with the following arguments:
--ssl_cert=/etc/my.cnf.d/certificates/client-cert.pem --ssl_key=/etc/my.cnf.d/certificates/client-key.pem --ssl_ca=/etc/my.cnf.d/certificates/ca.pem --ssl-verify-server-cert --max_allowed_packet=1GB

If it is installed on your system, then you can also check which options a given program is going to use by using the my_print_defaults utility and providing the names of the option groups that the program reads. For example:

my_print_defaults my_section client client-server client-mariadb
--ssl_cert=/etc/my.cnf.d/certificates/client-cert.pem
--ssl_key=/etc/my.cnf.d/certificates/client-key.pem
--ssl_ca=/etc/my.cnf.d/certificates/ca.pem
--ssl-verify-server-cert
--max_allowed_packet=1GB

See Configuring MariaDB with Option Files: Checking Program Options for more information.

MySQL 5.6 Obfuscated Authentication Credential Option File

MySQL 5.6 and above support an obfuscated authentication credential option file called .mylogin.cnf that is created with mysql_config_editor.

MariaDB Connector/C does not support this. The passwords in MySQL's .mylogin.cnf are only obfuscated, rather than encrypted, so the feature does not really add much from a security perspective. It is more likely to give users a false sense of security, rather than to seriously protect them.

Options

MariaDB Connector/C options can be set in client option groups.

Unlike with the server, dashes (-) and underscores (_) in options are not interchangeable for MariaDB Connector/C. Options must be specified exactly as they are defined. See CONC-395 for more information.

Unlike with the server, the loose prefix has no meaning for MariaDB Connector/C. Unknown options will simply be ignored.

Custom Options

MariaDB Connector/C allows application developers to implement custom options in option files by defining a function that matches this signature:

my_bool (*set_option)(MYSQL *mysql, const char *config_option, const char *config_value);

And then assigning the function pointer to mysql->options.extension->set_option.

Default Options

These are the options supported in option files by MariaDB Connector/C by default.

These options can also be set inside your application with the mysql_optionsv function.

bind-address

• Description: Specify the network interface from which to connect to MariaDB Server.

• mysql_optionsv: MYSQL_OPT_BIND

• Data Type: string

• Default Value:

• Introduced: MariaDB Connector/C 3.0.0

character-sets-dir

• Description: Directory for character set files.

• mysql_optionsv: MYSQL_SET_CHARSET_DIR

• Data Type: string

• Default Value:

compress

• Description: Compress all information sent between the client and the server if both support compression.

• mysql_optionsv: MYSQL_OPT_COMPRESS

• Data Type: boolean

• Default Value: false

connect-timeout, timeout

• Description: Connect timeout in seconds. This value will be passed as an unsigned int parameter.

• mysql_optionsv: MYSQL_OPT_CONNECT_TIMEOUT

• Data Type: int

• Default Value:

database

• Description: Database to use.

• mysql_optionsv: MARIADB_OPT_SCHEMA

• Data Type: string

• Default Value:

debug

• Description:

• mysql_optionsv: MARIADB_OPT_DEBUG

• Data Type: string

• Default Value:

default-auth

• Description: Default authentication client-side plugin to use.

• mysql_optionsv: MYSQL_DEFAULT_AUTH

• Data Type: string

• Default Value:

default-character-set

• Description: Specify the default character set for the connection.

• mysql_optionsv: MYSQL_SET_CHARSET_NAME

• Data Type: string

• Default Value:

disable-local-infile

• Description: Disable the use of LOAD DATA LOCAL INFILE.

• mysql_optionsv: N/A

• Data Type: string

• Default Value:

host

• Description: Hostname or IP address of the server to connect to.

• mysql_optionsv: MARIADB_OPT_HOST

• Data Type: string

• Default Value:

interactive-timeout

• Description:

• mysql_optionsv: MARIADB_OPT_INTERACTIVE

• Data Type: none

• Default Value:

init-command

• Description: Command(s) which will be executed when connecting and reconnecting to the server.

• mysql_optionsv: MYSQL_INIT_COMMAND

• Data Type: string

• Default Value:

local-infile

• Description: Enable or disable the use of LOAD DATA LOCAL INFILE.

• mysql_optionsv: MYSQL_OPT_LOCAL_INFILE

• Data Type: boolean

• Default Value: false

max-allowed-packet

• Description: The maximum packet length to send to or receive from server. The default is 16MB, the maximum 1GB.

• mysql_optionsv: MYSQL_OPT_MAX_ALLOWED_PACKET

• Data Type: size_t

• Default Value:

multi-results

• Description: Indicates that the client is able to handle multiple result sets from stored procedures or multi statements. This option will be automatically set if multi-statements is set.

• mysql_optionsv: MARIADB_OPT_MULTI_RESULTS

• Data Type: none

• Default Value:

multi-statements, multi-queries

• Description: Allows the client to send multiple statements in one command. Statements will be divided by a semicolon.

• mysql_optionsv: MARIADB_OPT_MULTI_STATEMENTS

• Data Type: string

• Default Value:

net-buffer-length

• Description: The buffer size for TCP/IP and socket communication. Default is 16KB.

• mysql_optionsv: MYSQL_OPT_NET_BUFFER_LENGTH

• Data Type: size_t

• Default Value:

• Introduced: MariaDB Connector/C 3.0.0

password

• Description: Password of the user to login to the server.

• mysql_optionsv: MARIADB_OPT_PASSWORD

• Data Type: string

• Default Value:

pipe

• Description: For Windows operating systems only: Use named pipes for client/server communication.

• mysql_optionsv: MYSQL_OPT_NAMED_PIPE

• Data Type: boolean

• Default Value: false

plugin-dir

• Description: Specify the location of client plugins.

  • The plugin directory can also be specified with the MARIADB_PLUGIN_DIR environment variable.

• mysql_optionsv: MYSQL_PLUGIN_DIR

• Data Type: string

• Default Value:

port

• Description: Port number to use for connection.

• mysql_optionsv: MARIADB_OPT_PORT

• Data Type: int

• Default Value: 3306

protocol

• Description: Specify the type of client/server protocol. Possible values are:

  • 0 - Refers to MYSQL_PROTOCOL_DEFAULT

  • 1 - Refers to MYSQL_PROTOCOL_TCP

  • 2 - Refers to MYSQL_PROTOCOL_SOCKET

  • 3 - Refers to MYSQL_PROTOCOL_PIPE

  • 4 - Refers to MYSQL_PROTOCOL_MEMORY

• mysql_optionsv: MYSQL_OPT_PROTOCOL

• Data Type: int

• Default Value:

reconnect

• Description: Enable or disable automatic reconnect.

• mysql_optionsv: MYSQL_OPT_RECONNECT

• Data Type: boolean

• Default Value: false

• Introduced: MariaDB Connector/C 3.0.0

report-data-truncation

• Description: Enable or disable reporting data truncation errors for prepared statements.

• mysql_optionsv: MYSQL_REPORT_DATA_TRUNCATION

• Data Type: boolean

• Default Value:

return-found-rows

• Description: Return the number of matched rows instead of number of changed rows.

• mysql_optionsv: MARIADB_OPT_FOUND_ROWS

• Data Type: none

• Default Value:

secure-auth

• Description: Refuse client connecting to server if it uses old (pre-MySQL4.1.1) protocol. Defaults to false (unlike MySQL since 5,6, which defaults to true).

• mysql_optionsv: MYSQL_SECURE_AUTH

• Data Type: boolean

• Default Value: false

server_public_key

• Description: Specifies the name of the file which contains the RSA public key of the database server. The format of this file must be in PEM format. This option is used by the caching_sha2_password client authentication plugin.

• mysql_optionsv: MYSQL_SERVER_PUBLIC_KEY

• Data Type: string

• Default Value:

• Introduced: MariaDB Connector/C 3.1.0

shared-memory-base-name

• Description: Shared-memory name to use for Windows connections using shared memory to a local server (started with the --shared-memory option). Case-sensitive.

• mysql_optionsv: MYSQL_SHARED_MEMORY_BASE_NAME

• Data Type: string

• Default Value:

socket

• Description: For connections to localhost, the Unix socket file to use, or, on Windows, the name of the named pipe to use.

• mysql_optionsv: MARIADB_OPT_UNIXSOCKET

• Data Type: string

• Default Value:

ssl-ca

• Description: Defines a path to a PEM file that should contain one or more X509 certificates for trusted Certificate Authorities (CAs) to use for TLS. This option requires that you use the absolute path, not a relative path.

  • See Secure Connections Overview: Certificate Authorities (CAs) for more information.

• mysql_optionsv: MYSQL_OPT_SSL_CA

• Data Type: string

• Default Value:

ssl-capath

• Description: Defines a path to a directory that contains one or more PEM files that should each contain one X509 certificate for a trusted Certificate Authority (CA) to use for TLS. This option requires that you use the absolute path, not a relative path. The directory specified by this option needs to be run through the openssl rehash command.

  • See Secure Connections Overview: Certificate Authorities (CAs) for more information.

  • This option is only supported if the connector was built with OpenSSL. If the connector was built with GnuTLS or Schannel, then this option is not supported. See TLS and Cryptography Libraries Used by MariaDB for more information about which libraries are used on which platforms.

• mysql_optionsv: MYSQL_OPT_SSL_CAPATH

• Data Type: string

• Default Value:

ssl-cert

• Description: Defines a path to the X509 certificate file to use for TLS. This option requires that you use the absolute path, not a relative path.

• mysql_optionsv: MYSQL_OPT_SSL_CERT

• Data Type: string

• Default Value:

ssl-cipher

• Description: List of permitted ciphers or cipher suites to use for TLS.

• mysql_optionsv: MYSQL_OPT_SSL_CIPHER

• Data Type: string

• Default Value:

ssl-crl

• Description: Defines a path to a PEM file that should contain one or more revoked X509 certificates to use for TLS. This option requires that you use the absolute path, not a relative path.

  • See Secure Connections Overview: Certificate Revocation Lists (CRLs) for more information.

  • This option is only supported if the connector was built with OpenSSL or Schannel. If the connector was built with GnuTLS, then this option is not supported. See TLS and Cryptography Libraries Used by MariaDB for more information about which libraries are used on which platforms.

• mysql_optionsv: MYSQL_OPT_SSL_CRL

• Data Type: string

• Default Value:

• Introduced: MariaDB Connector/C 3.1.1

ssl-crlpath

• Description: Defines a path to a directory that contains one or more PEM files that should each contain one revoked X509 certificate to use for TLS. This option requires that you use the absolute path, not a relative path. The directory specified by this option needs to be run through the openssl rehash command.

  • See Secure Connections Overview: Certificate Revocation Lists (CRLs) for more information.

  • This option is only supported if the connector was built with OpenSSL. If the connector was built with GnuTLS or Schannel, then this option is not supported. See TLS and Cryptography Libraries Used by MariaDB for more information about which libraries are used on which platforms.

• mysql_optionsv: MYSQL_OPT_SSL_CRLPATH

• Data Type: string

• Default Value:

• Introduced: MariaDB Connector/C 3.1.1

ssl-enforce

• Description: Whether to force TLS.

• mysql_optionsv: MYSQL_OPT_SSL_ENFORCE

• Data Type: boolean

• Default Value:

• Introduced: MariaDB Connector/C 3.1.1

ssl-fp

• Description: Specify the SHA1 fingerprint of a server certificate for validation during the TLS handshake.

• mysql_optionsv: MARIADB_OPT_SSL_FP

• Data Type: string

• Default Value:

• Introduced: MariaDB Connector/C 3.0.0

ssl-fp-list, ssl-fplist

• Description: Specify a file which contains one or more SHA1 fingerprints of server certificates for validation during the TLS handshake.

• mysql_optionsv: MARIADB_OPT_SSL_FP_LIST

• Data Type: string

• Default Value:

• Introduced: MariaDB Connector/C 3.0.0

ssl-key

• Description: Defines a path to a private key file to use for TLS. This option requires that you use the absolute path, not a relative path. If the key is protected with a passphrase, the passphrase needs to be specified with ssl-passphrase option.

• mysql_optionsv: MYSQL_OPT_SSL_KEY

• Data Type: string

• Default Value:

ssl-passphrase

• Description: Specify a passphrase for a passphrase-protected private key, as configured by the ssl-key option.

  • This option is only supported if the connector was built with OpenSSL or GnuTLS. If the connector was built with Schannel, then this option is not supported. See TLS and Cryptography Libraries Used by MariaDB for more information about which libraries are used on which platforms.

• mysql_optionsv: MARIADB_OPT_TLS_PASSPHRASE

• Data Type: string

• Default Value:

• Introduced: MariaDB Connector/C 3.0.0

ssl-verify-server-cert

• Description: Enables (or disables) server certificate verification.

• mysql_optionsv: MYSQL_OPT_SSL_VERIFY_SERVER_CERT

• Data Type: boolean

• Default Value:

• Introduced: MariaDB Connector/C 3.0.0

tls_version

• Description: Defines which TLS protocol versions are allowed. This should be a comma-separated list of TLS protocol versions to allow. Valid TLS protocol versions are TLSv1.0, TLSv1.1, TLSv1.2, and TLSv1.3. Both the client and server should support the allowed TLS protocol versions. See Secure Connections Overview: TLS Protocol Version Support for information on which TLS libraries support which TLS protocol versions. See TLS and Cryptography Libraries Used by MariaDB for more information about which TLS libraries are used on which platforms.

• mysql_optionsv: MARIADB_OPT_TLS_VERSION

• Data Type: string

• Default Value:

• Introduced: MariaDB Connector/C 3.0.4

user

• Description: User to login to the server.

• mysql_optionsv: MARIADB_OPT_USER

• Data Type: string

• Default Value:

See Also

• Configuring MariaDB with Option Files

These are currently documented on the github wiki.

This page describes the public data structures used by MariaDB Connector/C.

MYSQL

The MYSQL structure represents one database connection and is used by most of MariaDB Connector/C's API functions. The MYSQL structure needs to be allocated and initialized by the mysql_init() API function. It will be released by the mysql_close() function.

MYSQL_RES

The MYSQL_RES structure represents a result set which contains data and metadata information. It will be returned by the mysql_use_result(), mysql_store_result() and mysql_stmt_result_metadata() API functions and needs to be released by mysql_free_result().

MYSQL_ROW

MYSQL_ROW represents an array of character pointers, pointing to the columns of the actual data row. Data will be received by the mysql_fetch_row() function. The size of the array is the number of columns for the current row.

MYSQL_STMT

The MYSQL_STMT structure represents a prepared statement handle and is used by MariaDB Connector/C's prepared statement API functions. The MYSQL_STMT structure needs to be allocated and initialized by the mysql_stmt_init() function and needs to be released by the mysql_stmt_close() function.

MYSQL_FIELD

The MYSQL_FIELD structure describes the metadata of a column. It can be obtained by the mysql_fetch_field() function.

It has the following members:

MYSQL_BIND

The MYSQL_BIND structure is used to provide parameters for prepared statements or to receive output column value from prepared statements.

MYSQL_TIME

The MYSQL_TIME structure is used for date and time values in prepared statements. It has the following members:

MariaDB Connector/C functionality can be extended via loadable (or statically compiled in) plugins. As of the version 3.1.11 Connector/C comes with the following plugins

connection plugins

aurora

replication

pvio plugins

These plugins are used by the Connector/C to communicate with the MariaDB server.

socket

npipe

shmem

io plugins

These are plugins that are used whenever Connector/C needs to read a file. For example, for LOAD DATA LOCAL INFILE statement, when a server requests the Connector/C to send a specific file.

remote_io

This plugin uses libcurl to access remote files, it allows the client to execute statements like

LOAD DATA LOCAL INFILE 'http://mariadb.com/example.csv' INTO t1

Note that here, like with any LOAD DATA LOCAL, it'll be the client that fetches the file, not the server.

This plugin supports the following url schemes: http://, https://, ftp://, sftp://, ldap://, smb://.

auth plugins

These are authentication plugins. They are loaded automatically by the Connector/C when the server requests a specific authentication method.

mysql_native_password

dialog

This is a generic dialog plugin that asks the user a question (as instructed by the server) and sends the answer to the server. Everything is sent in plain text, one should enable SSL if secrets are sent via this plugin. Graphical clients can customize the plugin to provide graphical dialog form. See

client_ed25519

caching_sha2_password

sha256_password

auth_gssapi_client

mysql_old_password

mysql_clear_password

MariaDB Connector/C provides the following types and definitions.

Enumeration Types

enum mysql_option

enum mysql_option is used as a parameter in mysql_optionsv() and mysql_get_optionsv() API functions. For a list of integral constants and their meanings please check the documentation of mysql_get_optionsv().

enum enum_mysql_timestamp_type

enum enum_mysql_timestamp_type is used in the MYSQL_TIME structure and indicates the type. It has the following constants:

• MYSQL_TIMESTAMP_NONE

• MYSQL_TIMESTAMP_ERROR

• MYSQL_TIMESTAMP_DATE

• MYSQL_TIMESTAMP_DATETIME

• MYSQL_TIMESTAMP_TIME

enum mysql_set_option

enum mysql_set_option is used as a parameter in mysql_set_server_option() and has the following constants:

• MYSQL_OPTIONS_MULTI_STATEMENTS_ON

• MYSQL_OPTIONS_MULTI_STATEMENTS_OFF

enum enum_field_types

enum field_types describes the different field types used by MariaDB ] and has the following constants:

• MYSQL_TYPE_DECIMAL

• MYSQL_TYPE_TINY

• MYSQL_TYPE_SHORT

• MYSQL_TYPE_LONG

• MYSQL_TYPE_FLOAT

• MYSQL_TYPE_DOUBLE

• MYSQL_TYPE_NULL

• MYSQL_TYPE_TIMESTAMP

• MYSQL_TYPE_LONGLONG

• MYSQL_TYPE_INT24

• MYSQL_TYPE_DATE

• MYSQL_TYPE_TIME

• MYSQL_TYPE_DATETIME

• MYSQL_TYPE_YEAR

• MYSQL_TYPE_NEWDATE

• MYSQL_TYPE_VARCHAR

• MYSQL_TYPE_BIT

• MYSQL_TYPE_TIMESTAMP2

• MYSQL_TYPE_DATETIME2

• MYSQL_TYPE_TIME2

• MYSQL_TYPE_JSON

• MYSQL_TYPE_NEWDECIMAL

• MYSQL_TYPE_ENUM

• MYSQL_TYPE_SET

• MYSQL_TYPE_TINY_BLOB

• MYSQL_TYPE_MEDIUM_BLOB

• MYSQL_TYPE_LONG_BLOB

• MYSQL_TYPE_BLOB

• MYSQL_TYPE_VAR_STRING

• MYSQL_TYPE_STRING

• MYSQL_TYPE_GEOMETRY

enum mysql_enum_shutdown_level

enum mysql_enum_shutdown_level is used as a parameter in mysql_server_shutdown() and has the following constants:

• SHUTDOWN_DEFAULT

• KILL_QUERY

• KILL_CONNECTION

enum enum_stmt_attr_type

enum_stmt_attr_type is used to set different statement options. For a detailed description please check mysql_stmt_attr_set() function.

enum enum_cursor_type

enum_cursor_type specifies the cursor type and is used in mysql_stmt_attr_set() function. Currently the following constants are supported:

• CURSOR_TYPE_READ_ONLY

• CURSOR_TYPE_NO_CURSOR

enum enum_indicator_type

enum_indicator_type describes the type of indicator used for prepared statements bulk operations.

Definitions

Field Flags

The following field flags are used in MYSQL_FIELD structure.

Server Status

The server_status can be obtained by the mariadb_get_infov() function using the MARIADB_CONNECTION_SERVER_STATUS option.

Macros

After successful configuration, Connector/C can now be compiled.

Compiling on Windows

If no CMake generator was specified, CMake creates by default build files for Visual Studio. You can now either build Connector/C inside Visual Studio

devenv mariadb_connector_c.sln

or via command line

cmake --build . --config RelWithDebInfo

Compiling on Unix

By default CMake creates build files for GNU make. On some system GNU make is renamed to gmake. You can now build Connector/C with

make

or

cmake --build . --config Release

Configuration settings

Connector/C specifies its build process with platform-independent CMake listfiles included in each directory of a source tree with the name CMakeLists.txt. Configuration settings may be specified by passing the -D option to CMake command line interpreter.

Do not build Connector/C from root of the source tree: Either create a subdirectory "build" inside the source tree or create a subdirectory outside of the source tree.

Example:

cmake ../connector_c -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr/local

Reconfiguration

In case Connector/C was already configured, the CMakeCache.txt file needs to be removed first. In several cases, e.g. when cross compiling CMakeFiles subfolders need to be removed too.

Generator options

If you want to use a different generator, e.g. for nmake on Windows, you need to specify the generator with the -G option. cmake --help lists the available generators for the used platform.

CMake-related configuration settings

TLS/SSL options

Client plugins

Client plugins can be configured as dynamic plugins (DYNAMIC) or built-in plugins (STATIC) by specifying the plugin name followed by suffix _PLUGIN_TYPE as key, and "DYNAMIC" or "STATIC" as value.

E.g. for building dialog plugin as a built-in plugin, for versions < Connector/C 3.0.4

cmake .. -D{PLUGIN_NAME}_PLUGIN_TYPE=[STATIC|DYNAMIC|OFF]

Beginning with C/C 3.0.4

cmake .. -DCLIENT_PLUGIN_{PLUGIN_NAME}=[STATIC|DYNAMIC|OFF]

Connector/C 3.0 supports the following plugins:

Windows

• Visual Studio 2013 or newer (older versions of Visual Studio may also work but have not been tested).

• cmake 2.8.12 or newer, available from the CMake website.

• for Connector/C 2.x: OpenSSL libraries and include files.

• for Connector/C 3.0 remote-io plugin: Curl libraries and include files

Linux / Mac OS X

The following is a list of tools that are required for building MariaDB Connector/C on Linux and Mac OS X. Most, if not all, of these will exist as packages in your distribution's package repositories, so check there first.

• gcc 3.4.6 or newer C compiler

• TLS/SSL libraries and include files

  • OpenSSL 1.0.1 or newer or

  • GnuTLS 3.4 or newer

• cmake 2.8.12 or newer, available from the CMake website.

• for Connector/C 3.0 remote-io plugin: Curl libraries and include files

• For GSSAPI plugin: Kerberos V5 libraries

On Linux you can get those programs with your package manager. On Mac OS X you will need Xcode and to install the remaining programs with Fink or MacPorts.

Syntax

int mariadb_cancel(MYSQL * mysql);

mysql - mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

Immediately aborts a connection by making all subsequent read/write operations fail.mariadb_cancel() does not invalidate memory used for mysql structure, nor close any communication channels. To free the memory, mysql_close() must be called.mariadb_cancel() is useful to break long queries in situations where sending KILL is not possible.

mariadb_cancel() was added in Connector/C 3.0

Syntax

int mariadb_get_infov(MYSQL * mysql,
                      enum mariadb_value value,
                      void * arg,
                      ...);

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect(). For general information which is not bound to connection this parameter might be null.

• value - the type of value you want to retrieve. See description below.

• arg - pointer to a variable for storing value of the specified option.

• ... - variable argument list

Description

Retrieves generic or connection specific information.

Returns zero on success, non zero if an error occurred (invalid option),

This function was added in MariaDB Connector/C 3.0,

Value types

Generic information

For these information types parameter mysql needs to be set to NULL.

• MARIADB_CHARSET_NAME: Retrieves the charset information for a character set by it's literal representation.Parameter type: const MARIADB_CHARSET_INFO*.

• MARIADB_CLIENT_ERRORS: Retrieve array of client errors. This can be used in plugins to set global error messages (which are not exported by MariaDB Connector/C).Parameter type: const char **.

• MARIADB_CLIENT_VERSION: The client version in literal representation.Parameter type: const char *.

• MARIADB_CLIENT_VERSION_ID: The client version in numeric format.Parameter type: unsigned int.

• MARIADB_MAX_ALLOWED_PACKET: Retrieves value of maximum allowed packet size.Parameter type: size_t

• MARIADB_NET_BUFFER_LENGTH: Retrieves the length of net buffer.Parameter type: size_t

• MARIADB_TLS_LIBRARY: The TLS library MariaDB Connector/C is compiled against.Parameter type: const char *.

Connection related information

• MARIADB_CONNECTION_ASYNC_TIMEOUT: Retrieves the timeout for non blocking calls in seconds.Parameter type: unsigned int.

• MARIADB_CONNECTION_ASYNC_TIMEOUT_MS: Retrieves the timeout for non blocking calls in milliseconds.Parameter type: unsigned int.

• MARIADB_CONNECTION_MARIADB_CHARSET_INFO: Retrieves character set information for given connection. Parameter type: const MY_CHARSET_INFO *.

• MARIADB_CONNECTION_CLIENT_CAPABILITIES: Returns the capability flags of the client.Parameter type: unsigned long.

• MARIADB_CONNECTION_ERROR: Retrieves error message for last used command. Parameter type: const char *.

• MARIADB_CONNECTION_ERROR_ID: Retrieves error number for last used command. Parameter type: unsigned int.

• MARIADB_CONNECTION_EXTENDED_SERVER_CAPABILITIES: Returns the extended capability flags of the connected MariaDB server.Parameter type: unsigned long.

• MARIADB_CONNECTION_HOST: Retrieves connection's host name. Parameter type: const char *.

• MARIADB_CONNECTION_INFO: Retrieves generic info for last used command.Parameter type: const char *.

• MARIADB_CONNECTION_PORT: Retrieves the port number of server host.Parameter type: unsigned int.

• MARIADB_CONNECTION_PROTOCOL_VERSION_ID: Retrieves the protocol version number.Parameter type: unsigned int.

• MARIADB_CONNECTION_PVIO_TYPE: Retrives the pvio plugin used for specified connection.Parameter type: unsigned int.

• MARIADB_CONNECTION_SCHEMA: Retrieves the current schema.Parameter type: const char*.

• MARIADB_CONNECTION_SERVER_CAPABILITIES: Returns the capability flags of the connected server.Parameter type: unsigned long.

• MARIADB_CONNECTION_SERVER_STATUS: Returns server status after last operation. A list of possible flags can be found in the description OK packet.Parameter type: unsigned int.

• MARIADB_CONNECTION_SERVER_TYPE: Retrieves the type of the server.Parameter type: const char*.

• MARIADB_CONNECTION_SERVER_VERSION: Retrieves the server version in literal format.Parameter type: const char *.

• MARIADB_CONNECTION_SERVER_VERSION_ID: Retrieves the server version in numeric format.Parameter type: unsigned int.

• MARIADB_CONNECTION_SOCKET: Retrieves the handle (socket) for given connection.Parameter type: my_socket.

• MARIADB_CONNECTION_SQLSTATE: Retrieves current sqlstate information for last used command. Parameter type: const char *.

• MARIADB_CONNECTION_SSL_CIPHER: Retrieves the TLS cipher in use.Parameter type: const char *.

• MARIADB_CONNECTION_TLS_VERSION: Retrieves the TLS protocol version used in literal format.Parameter type: char *.

• MARIADB_CONNECTION_TLS_VERSION_ID: Retrieves the TLS protocol version used in numeric format.Parameter type: unsigned int.

• MARIADB_CONNECTION_UNIX_SOCKET: Retrieves the file name of the unix socketParameter type: const char *.

• MARIADB_CONNECTION_USER: Retrieves connection's user name.Parameter type: const char *.

Examples

/* get server port for current connection */
unsigned int port;
mariadb_get_infov(mysql, MARIADB_CONNECTION_PORT, void *)&port);

/* get user name for current connection */
const char *user;
mariadb_get_infov(mysql, MARIADB_CONNECTION_USER, (void *)&user);

See also

• mysql_get_optionv()

Syntax

my_bool  mariadb_reconnect(MYSQL * mysql)

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

mariadb_reconnect() tries to reconnect to a server in case the connection died due to timeout or other errors. It uses the same credentials which were specified in mysql_real_connect().

The function will return 0 on sucess.

The function will return an error, if the option MYSQL_OPT_RECONNECT wasn't specified before.

This function was added in Connector/C 3.0.

See also

• mysql_real_connect()

• mysql_options()

Syntax

my_ulonglong mysql_affected_rows(MYSQL * mysql);

mysql is a connection identifier, which was previously allocated by mysql_init() or mysql_real_connect().

Description

Returns the number of affected rows by the last operation associated with mysql, if the operation was an "upsert" (INSERT, UPDATE, DELETE or REPLACE) statement, or UINT64_MAX (0xffffffffffffffff) if the last query failed.

See also

• mysql_num_rows()

Syntax

my_bool mysql_autocommit(MYSQL * mysql, my_bool auto_mode);

• mysql - a mysql handle, identifier, which was previously allocated by mysql_init() or mysql_real_connect().

• auto_mode - whether to turn autocommit on or not.

Description

Toggles autocommit mode on or off for the current database connection. Autocommit mode will be set if mode=1 or unset if mode=0. Returns zero on success, or nonzero if an error occurred. Parameters

Turning off autocommit in sql

SET AUTOCOMMIT=0;

Syntax

my_bool mysql_change_user(MYSQL * mysql,
                          const char * user,
                          const char * passwd,
                          const char * db);

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

• user - the user name for server authentication

• passwd - the password for server authentication

• db - the default database. If desired, the NULL value may be passed resulting in only changing the user and not selecting a database. To select a database in this case use the mysql_select_db() function.

Description

Changes the user and default database of the current connection.

In order to successfully change users a valid username and password parameters must be provided and that user must have sufficient permissions to access the desired database. If for any reason authorization fails, the current user authentication will remain.

Returns zero on success, nonzero if an error occured.

Syntax

const char * mysql_character_set_name(MYSQL * mysql);

mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

Returns the default client character set for the specified connection.

Syntax

void mysql_close(MYSQL * mysql);

mysql - mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

Closes a previously opened connection.

Syntax

my_bool mysql_commit(MYSQL * mysql);

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

Commits the current transaction for the specified database connection. Returns zero on success, nonzero if an error occurred.

See also

• mysql_rollback()

Syntax

void mysql_data_seek(MYSQL_RES * result,
                     my_ulonglong offset);

• result - a result set identifier returned by mysql_store_result().

• offset - the field offset. Must be between zero and the total number of rows minus one (0..mysql_num_rows - 1).

Description

The mysql_data_seek() function seeks to an arbitrary function result pointer specified by the offset in the result set. Returns zero on success, nonzero if an error occurred.

Syntax

void mysql_debug(const char * debug);

• debug - a string representing the debug operation to perform. See description below.

Description

Enables debug output for development and debug purposes by using Fred Fish's DBUG library. For using this function the mariadb-client library must be compiled with debug support.

Almost all MariaDB binaries use the DBUG library and one can get a trace of the program execution by using the --debug command line option with the binary. This will only work if the binary is compiled for debugging (compiler option -DDBUG_ON).

Returns void.

The debug control string is a sequence of colon separated fields as follows:

field_1:field_2:field_n

Each field consists of a mandatory flag character followed by an optional "," and comma separated list of modifiers:

flag[,modifier,modifier,...,modifier]

The currently recognized flag characters are:

See also

• mysql_debug_end()

• mysql_dump_debug_info()

Syntax

int mysql_dump_debug_info(MYSQL * mysql);

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

This function is designed to be executed by an user with the SUPER privilege and is used to dump server status information into the log for the MariaDB Server relating to the connection.

Returns zero on success, nonzero if an error occurred.

See also

• mysql_debug()

• mysql_debug_end()

Syntax

unsigned int mysql_errno(MYSQL * mysql);

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

Returns the last error code for the most recent function call that can succeed or fail. Zero means no error occurred.

See also

• mysql_error()

• mysql_sqlstate()

Syntax

const char * mysql_error(MYSQL * mysql);

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

Returns the last error message for the most recent function call that can succeed or fail. If no error occurred an empty string is returned.

See also

• mysql_errno()

• mysql_sqlstate().

Syntax

unsigned long mysql_escape_string(char * to,
                                  const char * from,
                                  unsigned long);

Description

Escapes a string using the default character set.

See also

• mysql_real_escape_string()

Syntax

MYSQL_FIELD * mysql_fetch_field(MYSQL_RES * result);

• result - a result set identifier returned by mysql_store_result() or mysql_use_result().

Description

Returns the definition of one column of a result set as a pointer to a MYSQL_FIELD structure. Call this function repeatedly to retrieve information about all columns in the result set.

See also

• mysql_field_seek()

• mysql_field_tell()

• mysql_fetch_field_direct()

• mysql_store_result()

• mysql_use_result()

Syntax

MYSQL_FIELD * mysql_fetch_field_direct(MYSQL_RES * res,
                                       unsigned int fieldnr);

• res - a result set identifier returned by mysql_store_result() or mysql_use_result().

• fieldnr - the field number. This value must be within the range from 0 to number of fields - 1

Description

Returns a pointer to a MYSQL_FIELD structure which contains field information from the specified result set.

See also

• mysql_fetch_field()

• mysql_field_count()

Syntax

MYSQL_FIELD * mysql_fetch_fields(MYSQL_RES * res);

• res - a result set identifier returned by mysql_store_result() or mysql_use_result().

Description

This function serves an identical purpose to the mysql_fetch_field() function with the single difference that instead of returning one field at a time for each field, the fields are returned as an array. Each field contains the definition for a column of the result set.

See also

• mysql_fetch_field()

• mysql_fetch_field_direct()

• mysql_field_count()

Syntax

unsigned long * mysql_fetch_lengths(MYSQL_RES * result);

• result - a result set identifier returned by mysql_store_result() or mysql_use_result().

Description

The mysql_fetch_lengths() function returns an array containing the lengths of every column of the current row within the result set (not including terminating zero character) or NULL if an error occurred.

See also

• mysql_fetch_row()

Syntax

MYSQL_ROW mysql_fetch_row(MYSQL_RES * result);

• result - a result set identifier returned by mysql_store_result() or mysql_use_result().

Description

Fetches one row of data from the result set and returns it as an array of char pointers (MYSQL_ROW), where each column is stored in an offset starting from 0 (zero). Each subsequent call to this function will return the next row within the result set, or NULL if there are no more rows.

See also

• mysql_use_result()

• mysql_store_result()

Syntax

unsigned int mysql_field_count(MYSQL * mysql);

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

Description

Returns the number of columns for the most recent query on the connection represented by the link parameter as an unsigned integer. This function can be useful when using the mysql_store_result() function to determine if the query should have produced a non-empty result set or not without knowing the nature of the query.

See also

• mysql_store_result()

• mysql_use_result()

Syntax

MYSQL_FIELD_OFFSET mysql_field_seek(MYSQL_RES * result,
                                    MYSQL_FIELD_OFFSET offset);

• result - a result set identifier returned by mysql_store_result() or mysql_use_result().

• offset - the field number. This number must be in the range from 0..number of fields - 1.

Description

Sets the field cursor to the given offset. The next call to mysql_fetch_field() will retrieve the field definition of the column associated with that offset.

Returns the previous value of the field cursor.

See also

• mysql_field_tell()

Syntax

MYSQL_FIELD_OFFSET mysql_field_tell(MYSQL_RES * result);

• result - a result set identifier returned by mysql_store_result() or mysql_use_result().

Description

Return the offset of the field cursor used for the last mysql_fetch_field() call. This value can be used as a parameter for the function mysql_field_seek().

Returns the current offset of the field cursor

See also

• mysql_field_seek()

Syntax

void mysql_free_result(MYSQL_RES * result);

• result - a result set identifier returned by mysql_store_result() or mysql_use_result().

Description

Frees the memory associated with a result set. Returns void.

See also

• mysql_store_result()

• mysql_use_result()

Syntax

void mysql_get_character_set_info(MYSQL * mysql,
                                  MY_CHARSET_INFO * charset);

• mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().

• charset - a pointer to a MY_CHARSET_INFO structure, in which the information will be copied.

Description

Returns information about the current default character set for the specified connection.

Syntax

const char * mysql_get_client_info(void );

Description

Returns a string representing the client library version

See also

• mysql_get_client_version()

• mysql_get_host_info()

• mysql_get_proto_info()

Syntax