5.2 Connector/ODBC Connection Parameters

You can specify the parameters in the following tables for Connector/ODBC when configuring a DSN:

• Table 5.1, “Connector/ODBC DSN Configuration Options”

• Table 5.3, “Connector/ODBC Option Parameters”

Users on Windows can use the ODBC Data Source Administrator to set these parameters; see Section 5.3, “Configuring a Connector/ODBC DSN on Windows” on how to do that, and see Table 5.1, “Connector/ODBC DSN Configuration Options” for information on the options and the fields and check boxes they corrrespond to on the graphical user interface of the ODBC Data Source Administrator. On Unix and OS X, use the parameter name and value as the keyword/value pair in the DSN configuration. Alternatively, you can set these parameters within the InConnectionString argument in the SQLDriverConnect() call.

Table 5.1 Connector/ODBC DSN Configuration Options

Parameter	GUI Option	Default Value	Comment
user	User	ODBC	The user name used to connect to MySQL.
uid	User	ODBC	Synonymous with user. Added in 3.51.16.
server	TCP/IP Server	localhost	The host name of the MySQL server.
database	Database	-	The default database.
option	-	0	Options that specify how Connector/ODBC works. See Table 5.3, “Connector/ODBC Option Parameters” and Table 5.4, “Recommended Connector/ODBC Option Values for Different Configurations”.
port	Port	3306	The TCP/IP port to use if server is not localhost.
initstmt	Initial Statement	-	Initial statement. A statement to execute when connecting to MySQL. In version 3.51 the parameter is called stmt. The driver supports the initial statement being executed only at the time of the initial connection.
password	Password	-	The password for the user account on server.
pwd	Password	-	Synonymous with password. Added in 3.51.16.
socket	-	-	The Unix socket file or Windows named pipe to connect to if server is localhost.
sslca	SSL Certificate	-	The path to a file with a list of trust SSL CAs. Added in 3.51.16.
sslcapath	SSL CA Path	-	The path to a directory that contains trusted SSL CA certificates in PEM format. Added in 3.51.16.
sslcert	SSL Certificate	-	The name of the SSL certificate file to use for establishing a secure connection. Added in 3.51.16.
sslcipher	SSL Cipher	-	A list of permissible ciphers to use for SSL encryption. The cipher list has the same format as the openssl ciphers command. Added in 3.51.16.
sslkey	SSL Key	-	The name of the SSL key file to use for establishing a secure connection. Added in 3.51.16.
rsakey	RSA Public Key	-	The full-path name of the PEM file that contains the RSA public key for using the SHA256 authentication plugin of MySQL. Added in 5.3.4.
sslverify	Verify SSL	0	If set to 1, the SSL certificate will be verified when used with the MySQL connection. If not set, then the default behavior is to ignore SSL certificate verification. Note The option has been deprecated since 5.3.7. It is preferable to use the SSLMODE option parameter instead.
charset	Character Set	-	The character set to use for the connection. Added in 3.51.17.
readtimeout	-	-	The timeout in seconds for attempts to read from the server. Each attempt uses this timeout value and there are retries if necessary, so the total effective timeout value is three times the option value. You can set the value so that a lost connection can be detected earlier than the TCP/IP Close_Wait_Timeout value of 10 minutes. This option works only for TCP/IP connections, and only for Windows prior to MySQL 5.1.12. Corresponds to the MYSQL_OPT_READ_TIMEOUT option of the MySQL Client Library. Added in 3.51.27.
writetimeout	-	-	The timeout in seconds for attempts to write to the server. Each attempt uses this timeout value and there are net_retry_count retries if necessary, so the total effective timeout value is net_retry_count times the option value. This option works only for TCP/IP connections, and only for Windows prior to MySQL 5.1.12. Corresponds to the MYSQL_OPT_WRITE_TIMEOUT option of the MySQL Client Library. Added in 3.51.27.
interactive	Interactive Client	0	If set to 1, the CLIENT_INTERACTIVE connection option of mysql-real-connect() is enabled. Added in 5.1.7.
prefetch	Prefetch from server by _ rows at a time	0	When set to a non-zero value N, causes all queries in the connection to return N rows at a time rather than the entire result set. Useful for queries against very large tables where it is not practical to retrieve the whole result set at once. You can scroll through the result set, N records at a time. This option works only with forward-only cursors. It does not work when the option parameter MULTI_STATEMENTS is set. It can be used in combination with the option parameter NO_CACHE. Its behavior in ADO applications is undefined: the prefetching might or might not occur. Added in 5.1.11.
no_ssps	-	0	In Connector/ODBC 5.2, by default, server-side prepared statements are used. When this option is set to a non-zero value, prepared statements are emulated on the client side, which is the same behavior as in 5.1 and 3.51. Added in 5.2.0.
can_handle_exp_pwd	Can Handle Expired Password	0	Indicates that the application can deal with an expired password, which is signalled by an SQL state of 08004 (“Server rejected the connection”) and a native error code ER_MUST_CHANGE_PASSWORD_LOGIN (1862). The connection is “sandboxed”, and can do nothing other than issue a SET PASSWORD statement. To establish a connection in this case, your application must either use the initstmt connection option to set a new password at the start, or issue a SET PASSWORD statement immediately after connecting. Once the expired password is reset, the restrictions on the connection are lifted. See ALTER USER Syntax for details about password expiration for MySQL server accounts. Added in 5.2.4.
ENABLE_CLEARTEXT_PLUGIN	Enable Cleartext Authentication	0	Enables cleartext authentication. Added in 5.1.13 and 5.2.5.
NO_TLS_1_0	Disable TLS 1.0	0	Disallows the use of TLS 1.0 for connection encryption. All versions of TLS are allowed by default, and this option excludes version 1.0 from being used. Added in 5.3.7.
NO_TLS_1_1	Disable TLS 1.1	0	Disallows the use of TLS 1.1 for connection encryption. All versions of TLS are allowed by default, and this option exudes version 1.1 from being used. Added in 5.3.7.
NO_TLS_1_2	Disable TLS 1.2	0	Disallows the use of TLS 1.2 for connection encryption. All versions of TLS are allowed by default, and this option exudes version 1.1 from being used. Added in 5.3.7.
SSL_ENFORCE	Enforce SSL	0	Enforce the requirement to use SSL for connections to server. See Table 5.2, “Combined Effects of SSL_ENFORCE and DISABLE_SSL_DEFAULT”. Added in 5.3.6. Note The option has been deprecated since 5.3.7. It is preferable to use the SSLMODE option parameter instead.
DISABLE_SSL_DEFAULT	Disable default SSL	0	Disable the default requirement to use SSL for connections to server. When set to “0” [default], Connector/ODBC tries to connect with SSL first, and falls back to unencrypted connection if it is not possible to establish an SSL connection. When set to “1,” Connection with SSL is not attempted, and unencrypted connection is used, unless SSL_ENFORCE is also set to “1.” See Table 5.2, “Combined Effects of SSL_ENFORCE and DISABLE_SSL_DEFAULT”. Added in 5.3.6. Note The option has been deprecated since 5.3.7. It is preferable to use the SSLMODE option parameter instead.
SSLMODE	SSL Mode	-	Sets the SSL mode of the server connection. The option can be set to any of the following values: DISABLED, PREFERRED, REQUIRED, VERIFY_CA, or VERIFY_IDENTITY. See description for the --ssl-mode option in the MySQL 5.7 Reference Manual for the meaning of each of the option values. If SSLMODE is not explicitly set, use of the sslca or sslcapath option implies SSLMODE=VERIFY_CA. Added in 5.3.7. This option overrides the deprecated sslverify and SSL_ENFORCE options.

Note

The SSL configuration parameters can also be automatically loaded from a my.ini or my.cnf file. See Using Option Files.

Table 5.2 Combined Effects of SSL_ENFORCE and DISABLE_SSL_DEFAULT

	DISABLE_SSL_DEFAULT = 0	DISABLE_SSL_DEFAULT = 1
SSL_ENFORCE = 0	(Default) Connection with SSL is attempted first; if not possible, fall back to unencrypted connection.	Connection with SSL is not attempted; use unencrypted connection.
SSL_ENFORCE = 1	Connect with SSL; throw an error if an SSL connection cannot be established.	Connect with SSL; throw an error if an SSL connection cannot be established. DISABLE_SSL_DEFAULT=1 is overridden.

The behavior of Connector/ODBC can be also modified by using special option parameters listed in Table 5.3, “Connector/ODBC Option Parameters”, specified in the connection string or through the GUI dialog box. All of the connection parameters also have their own numeric constant values, which can be added up as a combined value for the option parameter for specifying those options. However, the numerical option value in the connection string can only enable, but not disable parameters enabled on the DSN, which can only be overridden by specifying the option parameters using their text names in the connection string.

Note

While the combined numerical value for the option parameter can be easily constructed by addition of the options' constant values, decomposing the value to verify if particular options are enabled can be difficult. We recommend using the options' parameter names instead in the connection string, because they are self-explanatory.

Table 5.3 Connector/ODBC Option Parameters

Parameter Name	GUI Option	Constant Value	Description
FOUND_ROWS	Return matched rows instead of affected rows	2	The client cannot handle when MySQL returns the true value of affected rows. If this flag is set, MySQL returns “found rows” instead. You must have MySQL 3.21.14 or newer for this to work.
BIG_PACKETS	Allow big result set	8	Do not set any packet limit for results and bind parameters. Without this option, parameter binding will be truncated to 255 characters.
NO_PROMPT	Don't prompt when connecting	16	Do not prompt for questions even if driver would like to prompt.
DYNAMIC_CURSOR	Enable Dynamic Cursors	32	Enable or disable the dynamic cursor support.
NO_SCHEMA	Ignore schema in column specifications	64	Ignore use of database name in db_name.tbl_name.col_name.
NO_DEFAULT_CURSOR	Disable driver-provided cursor support	128	Force use of ODBC manager cursors (experimental).
NO_LOCALE	Don't use setlocale()	256	Disable the use of extended fetch (experimental).
PAD_SPACE	Pad CHAR to full length with space	512	Pad CHAR columns to full column length.
FULL_COLUMN_NAMES	Include table name in SQLDescribeCol()	1024	SQLDescribeCol() returns fully-qualified column names.
COMPRESSED_PROTO	Use compression	2048	Use the compressed client/server protocol.
IGNORE_SPACE	Ignore space after function names	4096	Tell server to ignore space after function name and before “(” (needed by PowerBuilder). This makes all function names keywords.
NAMED_PIPE	Named Pipe	8192	Connect with named pipes to a mysqld server running on NT.
NO_BIGINT	Treat BIGINT columns as INT columns	16384	Change BIGINT columns to INT columns (some applications cannot handle BIGINT).
NO_CATALOG	Disable catalog support	32768	Forces results from the catalog functions, such as SQLTables, to always return NULL and the driver to report that catalogs are not supported.
USE_MYCNF	Read options from my.cnf	65536	Read parameters from the [client] and [odbc] groups from my.cnf.
SAFE	Enable safe options	131072	Add some extra safety checks.
NO_TRANSACTIONS	Disable transaction support	262144	Disable transactions.
LOG_QUERY	Log queries to %TEMP%\myodbc.sql	524288	Enable query logging to c:\myodbc.sql(/tmp/myodbc.sql) file. (Enabled only in debug mode.)
NO_CACHE	Don't cache results of forward-only cursors	1048576	Do not cache the results locally in the driver, instead read from server (mysql_use_result()). This works only for forward-only cursors. This option is very important in dealing with large tables when you do not want the driver to cache the entire result set.
FORWARD_CURSOR	Force use of forward-only cursors	2097152	Force the use of Forward-only cursor type. In cases of applications setting the default static/dynamic cursor type and one wants the driver to use noncache result sets, this option ensures the forward-only cursor behavior.
AUTO_RECONNECT	Enable automatic reconnect	4194304	Enables auto-reconnection functionality. Do not use this option with transactions, since an auto-reconnection during a incomplete transaction may cause corruption. An auto-reconnected connection will not inherit the same settings and environment as the original connection. Added in 3.51.13.
AUTO_IS_NULL	Enable SQL_AUTO_IS_NULL	8388608	When AUTO_IS_NULL is set, the driver does not change the default value of sql_auto_is_null, leaving it at 1, so you get the MySQL default, not the SQL standard behavior. When AUTO_IS_NULL is not set, the driver changes the default value of SQL_AUTO_IS_NULL to 0 after connecting, so you get the SQL standard, not the MySQL default behavior. Thus, omitting the flag disables the compatibility option and forces SQL standard behavior. See IS NULL. Added in 3.51.13.
ZERO_DATE_TO_MIN	Return SQL_NULL_DATA for zero date	16777216	Translates zero dates (XXXX-00-00) into the minimum date values supported by ODBC, XXXX-01-01. This resolves an issue where some statements will not work because the date returned and the minimum ODBC date value are incompatible. Added in 3.51.17.
MIN_DATE_TO_ZERO	Bind minimal date as zero date	33554432	Translates the minimum ODBC date value (XXXX-01-01) to the zero date format supported by MySQL (XXXX-00-00). This resolves an issue where some statements will not work because the date returned and the minimum ODBC date value are incompatible. Added in 3.51.17.
MULTI_STATEMENTS	Allow multiple statements	67108864	Enables support for batched statements. Added in 3.51.18.
COLUMN_SIZE_S32	Limit column size to signed 32-bit range	134217728	Limits the column size to a signed 32-bit value to prevent problems with larger column sizes in applications that do not support them. This option is automatically enabled when working with ADO applications. Added in 3.51.22.
NO_BINARY_RESULT	Always handle binary function results as character data	268435456	When set, this option disables charset 63 for columns with an empty org_table. Added in 3.51.26.
DFLT_BIGINT_BIND_STR	[This option is not on the GUI dialog box]	536870912	Causes BIGINT parameters to be bound as strings. Microsoft Access treats BIGINT as a string on linked tables. The value is read correctly, but bound as a string. This option is used automatically if the driver is used by Microsoft Access. Added in 5.1.3.
NO_INFORMATION_SCHEMA	Don't use INFORMATION_SCHEMA for metadata	1073741824	Tells catalog functions not to use INFORMATION_SCHEMA, but rather use legacy algorithms. The trade-off here is usually speed for information quality. Using INFORMATION_SCHEMA is often slow, but the information obtained is more complete. Added in 5.1.7.

Table 5.4, “Recommended Connector/ODBC Option Values for Different Configurations” shows some recommended parameter settings and their corresponding option values for various configurations:

Table 5.4 Recommended Connector/ODBC Option Values for Different Configurations

Configuration	Parameter Settings	Option Value
Microsoft Access, Visual Basic	FOUND_ROWS=1;	2
Microsoft Access (with improved DELETE queries)	FOUND_ROWS=1;DYNAMIC_CURSOR=1;	34
Microsoft SQL Server	COLUMN_SIZE_S32=1;	134217728
Large tables with too many rows	COMPRESSED_PROTO=1;	2048
Sybase PowerBuilder	IGNORE_SPACE=1;FLAG_SAFE=1;	135168
Query log generation (Debug mode)	LOG_QUERY=1;	524288
Large tables with no-cache results	NO_CACHE=1;FORWARD_CURSOR=1;	3145728
Applications that run full-table "SELECT * FROM ... " query, but read only a small number (N) of rows from the result	PREFETCH=N	Not Applicable