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MySQL 3.23, 4.0, 4.1 Reference Manual :: 17 Connectors and APIs :: 17.2 MySQL Connector/NET :: 17.2.6 Connector/NET Connection String Options Reference
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17.2.6. Connector/NET Connection String Options Reference

Name Default Description
Allow Batch true When true, multiple SQL statements can be sent with one command execution. -Note- Starting with MySQL 4.1.1, batch statements should be separated by the server-defined separator character. Commands sent to earlier versions of MySQL should be separated with ';'.
Allow User Variables false Setting this to true indicates that the provider expects user variables in the SQL. This option was added in Connector/NET version 5.2.2.
Allow Zero Datetime false True to have MySqlDataReader.GetValue() return a MySqlDateTime for date or datetime columns that have illegal values. False will cause a System.DateTime object to be returned for legal values and an exception will be thrown for illegal values.
AutoEnlist true If AutoEnlist is set to true, which is the default, a connection opened using TransactionScope participates in this scope, it commits when the scope commits and rolls back if TransactionScope does not commit. However, this feature is considered security sensitive and therefore cannot be used in a medium trust environment.
BlobAsUTF8ExcludePattern null  
BlobAsUTF8IncludePattern null  
CertificateFile null This option specifies the path to a certificate file in PFX format. For an example of usage see Section 17.2.4.7, “Tutorial: Using SSL with MySQL Connector/NET”. Was introduced with 6.2.1.
CertificatePassword null This option allows you to specify a password which is used in conjunction with a certificate specified using the option CertificateFile. For an example of usage see Section 17.2.4.7, “Tutorial: Using SSL with MySQL Connector/NET”. Was introduced with 6.2.1.
Certificate Store Location null This option allows you to access a certificate held in a personal store, rather than use a certificate file and password combination. For an example of usage see Section 17.2.4.7, “Tutorial: Using SSL with MySQL Connector/NET”. Was introduced with 6.2.1.
Certificate Thumbprint null This option allows you to specify a certificate thumbprint to ensure correct identifcation of a certificate contained within a personal store. For an example of usage see Section 17.2.4.7, “Tutorial: Using SSL with MySQL Connector/NET”. Was introduced with 6.2.1.
CharSet, Character Set   Specifies the character set that should be used to encode all queries sent to the server. Resultsets are still returned in the character set of the data returned.
Connect Timeout, Connection Timeout 15 The length of time (in seconds) to wait for a connection to the server before terminating the attempt and generating an error.
Connection Reset false  
Convert Zero Datetime false True to have MySqlDataReader.GetValue() and MySqlDataReader.GetDateTime() return DateTime.MinValue for date or datetime columns that have illegal values.
Default Command Timeout 30 Sets the default value of the command timeout to be used. This does not supercede the individual command timeout property on an individual command object. If you set the command timeout property, that will be used. This option was added in Connector/NET 5.1.4
Encrypt, UseSSL false For Connector/NET 5.0.3 and later, when true, SSL encryption is used for all data sent between the client and server if the server has a certificate installed. Recognized values are true, false, yes, and no. In versions before 5.0.3, this option had no effect. From version 6.2.1 this option is deprecated and is replaced by SSL Mode. However, the option is still supported if used. If this option is set to true it is equivalent to SSL Mode = Preferred.
FunctionsReturnString false This will cause the connector to return binary/varbinary values as strings, if they do not have a tablename in the metadata.
Host, Server, Data Source, DataSource, Address, Addr, Network Address localhost The name or network address of the instance of MySQL to which to connect. Multiple hosts can be specified separated by &. This can be useful where multiple MySQL servers are configured for replication and you are not concerned about the precise server you are connecting to. No attempt is made by the provider to synchronize writes to the database so care should be taken when using this option. In Unix environment with Mono, this can be a fully qualified path to MySQL socket file name. With this configuration, the Unix socket will be used instead of TCP/IP socket. Currently only a single socket name can be given so accessing MySQL in a replicated environment using Unix sockets is not currently supported.
Ignore Prepare true When true, instructs the provider to ignore any calls to MySqlCommand.Prepare(). This option is provided to prevent issues with corruption of the statements when use with server side prepared statements. If you want to use server-side prepare statements, set this option to false. This option was added in Connector/NET 5.0.3 and Connector/NET 1.0.9.
Initial Catalog, Database mysql The name of the database to use intially
Interactive, InteractiveSession false If set to true the client is interactive. An interactive client is one where the server variable CLIENT_INTERACTIVE is set. If an interactive client is set, the wait_timeout variable is set to the value of interactive_timeout. The client will then timeout after this period of inactivity. More details can be found in the server manual Section 5.1.3, “Server System Variables”.
Logging false When true, various pieces of information is output to any configured TraceListeners.
Old Guids false This option was introduced in Connector/NET 6.1.1. The backend representation of a GUID type was changed from BINARY(16) to CHAR(36). This was done to allow developers to use the server function UUID() to populate a GUID table - UUID() generates a 36-character string. Developers of older applications can add 'Old Guids=true' to the connection string in order to use a GUID of data type BINARY(16).
Old Syntax, OldSyntax false This option was deprecated in Connector/NET 5.2.2. All code should now be written using the '@' symbol as the parameter marker.
Password, pwd   The password for the MySQL account being used.
Persist Security Info false When set to false or no (strongly recommended), security-sensitive information, such as the password, is not returned as part of the connection if the connection is open or has ever been in an open state. Resetting the connection string resets all connection string values including the password. Recognized values are true, false, yes, and no.
Pipe Name, Pipe mysql When set to the name of a named pipe, the MySqlConnection will attempt to connect to MySQL on that named pipe.This settings only applies to the Windows platform.
Port 3306 The port MySQL is using to listen for connections. This value is ignored if Unix socket is used.
Procedure Cache Size 25 Sets the size of the stored procedure cache. By default, Connector/NET will store the metadata (input/output datatypes) about the last 25 stored procedures used. To disable the stored procedure cache, set the value to zero (0). This option was added in Connector/NET 5.0.2 and Connector/NET 1.0.9.
Protocol socket Specifies the type of connection to make to the server. Values can be: socket or tcp for a socket connection, pipe for a named pipe connection, unix for a Unix socket connection, memory to use MySQL shared memory.
Respect Binary Flags true Setting this option to false means that Connector/NET will ignore a column's binary flags as set by the server. This option was added in Connector/NET version 5.1.3.
Shared Memory Name MYSQL The name of the shared memory object to use for communication if the connection protocol is set to memory.
Sql Server Mode false Allow SQL Server syntax. When set to true allows Connector/NET to support square brackets around symbols instead of backticks. This allows Visual Studio wizards that bracket symbols with [] to work with Connector/NET. This option incurs a performance hit, so should only be used if necessary. This option was added in version 6.3.1.
SSL Mode None This option has the following values:

  • None - do not use SSL.

  • Preferred - use SSL if the server supports it, but allow connection in all cases.

  • Required - Always use SSL. Deny connection if server does not support SSL.

  • VerifyCA - Always use SSL. Validate the CA but tolerate name mismatch.

  • VerifyFull - Always use SSL. Fail if the host name is not correct.

This option was introduced in MySQL Connector/NET 6.2.1.

TreatBlobsAsUTF8 false  
Treat Tiny As Boolean true Setting this value to false indicates that TINYINT(1) will be treated as an INT. See also Section 10.1.1, “Overview of Numeric Types” for a further explanation of the TINYINT and BOOL data types.
Use Affected Rows false When true the connection will report changed rows instead of found rows. This option was added in Connector/NET version 5.2.6.
Use Procedure Bodies true Setting this option to false indicates that the user connecting to the database does not have the SELECT privileges for the mysql.proc (stored procedures) table. When to set to false, Connector/NET will not rely on this information being available when the procedure is called. Because Connector/NET will be unable to determine this information, you should explicitly set the types of the all the parameters before the call and the parameters should be added to the command in the exact same order as they appear in the procedure definition. This option was added in Connector/NET 5.0.4 and Connector/NET 1.0.10.
User Id, Username, Uid, User name   The MySQL login account being used.
Use Compression false

Setting this option to true enables compression of packets exchanged between the client and the server. This exchange is defined by the MySQL client-server protocol.

Compression is used if both client and server support ZLIB compression, and the client has requested compression using this option.

A compressed packet header is: packet length (3 bytes), packet number (1 byte), and Uncompressed Packet Length (3 bytes). The Uncompressed Packet Length is the number of bytes in the original, uncompressed packet. If this is zero then the data in this packet has not been compressed. When the compression protocol is in use, either the client or the server may compress packets. However, compression will not occur if the compressed length is greater than the original length. Thus, some packets will contain compressed data while other packets will not.

Use Usage Advisor false  
Use Performance Monitor false  

The following table lists the valid names for connection pooling values within the ConnectionString. For more information about connection pooling, see Connection Pooling for the MySQL Data Provider.

Name Default Description
Cache Server Configuration, CacheServerConfiguration, CacheServerConfig false Specifies whether server variables should be updated when a pooled connection is returned. Turning this on will yield faster opens but will also not catch any server changes made by other connections.
Connection Lifetime 0 When a connection is returned to the pool, its creation time is compared with the current time, and the connection is destroyed if that time span (in seconds) exceeds the value specified by Connection Lifetime. This is useful in clustered configurations to force load balancing between a running server and a server just brought online. A value of zero (0) causes pooled connections to have the maximum connection timeout.
Max Pool Size 100 The maximum number of connections allowed in the pool.
Min Pool Size 0 The minimum number of connections allowed in the pool.
Pooling true When true, the MySqlConnection object is drawn from the appropriate pool, or if necessary, is created and added to the appropriate pool. Recognized values are true, false, yes, and no.
Reset Pooled Connections, ResetConnections, ResetPooledConnections true Specifies whether a ping and a reset should be sent to the server before a pooled connection is returned. Not resetting will yield faster connection opens but also will not clear out session items such as temp tables.