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25.1.3.6 Connecting Without a Predefined DSN »
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25.1.3.5. Connector/ODBC Connection Parameters

You can specify the parameters in the following tables for Connector/ODBC when configuring a DSN. Users on Windows can use the Options and Advanced panels when configuring a DSN to set these parameters; see the table for information on which options relate to which fields and checkboxes. On Unix and Mac 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.

Parameter Default Value Comment
user ODBC (on Windows) The username used to connect to MySQL.
server localhost The hostname of the MySQL server.
database   The default database.
option 0 Options that specify how Connector/ODBC should work. See below.
port 3306 The TCP/IP port to use if server is not localhost.
stmt   A statement to execute when connecting to MySQL.
password   The password for the user account on server.
socket   The Unix socket file or Windows named pipe to connect to if server is localhost.

The option argument is used to tell Connector/ODBC that the client isn't 100% ODBC compliant. On Windows, you normally select options by toggling the checkboxes in the connection screen, but you can also select them in the option argument. The following options are listed in the order in which they appear in the Connector/ODBC connect screen:

Value Windows Checkbox Description
1 Don't Optimized Column Width The client can't handle that Connector/ODBC returns the real width of a column.
2 Return Matching Rows The client can't handle that 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 to get this to work.
4 Trace Driver Calls To myodbc.log Make a debug log in C:\myodbc.log on Windows, or /tmp/myodbc.log on Unix variants.
8 Allow Big Results Don't set any packet limit for results and parameters.
16 Don't Prompt Upon Connect Don't prompt for questions even if driver would like to prompt.
32 Enable Dynamic Cursor Enable or disable the dynamic cursor support. (Not allowed in Connector/ODBC 2.50.)
64 Ignore # in Table Name Ignore use of database name in db_name.tbl_name.col_name.
128 User Manager Cursors Force use of ODBC manager cursors (experimental).
256 Don't Use Set Locale Disable the use of extended fetch (experimental).
512 Pad Char To Full Length Pad CHAR columns to full column length.
1024 Return Table Names for SQLDescribeCol SQLDescribeCol() returns fully qualified column names.
2048 Use Compressed Protocol Use the compressed client/server protocol.
4096 Ignore Space After Function Names Tell server to ignore space after function name and before ‘(’ (needed by PowerBuilder). This makes all function names keywords.
8192 Force Use of Named Pipes Connect with named pipes to a mysqld server running on NT.
16384 Change BIGINT Columns to Int Change BIGINT columns to INT columns (some applications can't handle BIGINT).
32768 No Catalog (exp) Return 'user' as Table_qualifier and Table_owner from SQLTables (experimental).
65536 Read Options From my.cnf Read parameters from the [client] and [odbc] groups from my.cnf.
131072 Safe Add some extra safety checks (should not be needed but...).
262144 Disable transaction Disable transactions.
524288 Save queries to myodbc.sql Enable query logging to c:\myodbc.sql(/tmp/myodbc.sql) file. (Enabled only in debug mode.)
1048576 Don't Cache Result (forward only cursors) 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 don't want the driver to cache the entire result set.
2097152 Force Use Of Forward Only Cursors Force the use of Forward-only cursor type. In case of applications setting the default static/dynamic cursor type, and one wants the driver to use non-cache result sets, then this option ensures the forward-only cursor behavior.
4194304 Enable auto-reconnect. Enables auto-reconnection functionality. You should not use this option with transactions, since a auto reconnection during a incomplete transaction may cause corruption. Note that an auto-reconnected connection will not inherit the same settings and environment as the original. This option was enabled in Connector/ODBC 3.5.13.
8388608 Flag Auto Is Null When set, this option causes the connection to set the SQL_AUTO_IS_NULL option to 1. This disables the standard behavior, but may enable older applications to correctly identify AUTO_INCREMENT values. For more information, see Capítulo 12, Funciones y operadores. This option was enabled in Connector/ODBC 3.5.13.

To select multiple options, add together their values. For example, setting option to 12 (4+8) gives you debugging without packet limits.

The following table shows some recommended option values for various configurations:

Configuration Option Value
Microsoft Access, Visual Basic 3
Driver trace generation (Debug mode) 4
Microsoft Access (with improved DELETE queries) 35
Large tables with too many rows 2049
Sybase PowerBuilder 135168
Query log generation (Debug mode) 524288
Generate driver trace as well as query log (Debug mode) 524292
Large tables with no-cache results 3145731

Ésta es una traducción del manual de referencia de MySQL, que puede encontrarse en dev.mysql.com. El manual de referencia original de MySQL está escrito en inglés, y esta traducción no necesariamente está tan actualizada como la versión original. Para cualquier sugerencia sobre la traducción y para señalar errores de cualquier tipo, no dude en dirigirse a mysql-es@vespito.com.