mysql的client_flags

今天在测试自己写的异步mysql库时发现mysql 居然不认schema.table这种格式的sql，折腾了好久才发现原来是client_flag导致的，因此将所有的client_flag参数列出来如下

#define CLIENT_LONG_PASSWORD    1   /* new more secure passwords */
#define CLIENT_FOUND_ROWS   2   /* Found instead of affected rows */
#define CLIENT_LONG_FLAG    4   /* Get all column flags */
#define CLIENT_CONNECT_WITH_DB  8   /* One can specify db on connect */
#define CLIENT_NO_SCHEMA    16  /* Don't allow database.table.column */
#define CLIENT_COMPRESS     32  /* Can use compression protocol */
#define CLIENT_ODBC     64  /* Odbc client */
#define CLIENT_LOCAL_FILES  128 /* Can use LOAD DATA LOCAL */
#define CLIENT_IGNORE_SPACE 256 /* Ignore spaces before '(' */
#define CLIENT_PROTOCOL_41  512 /* New 4.1 protocol */
#define CLIENT_INTERACTIVE  1024    /* This is an interactive client */
#define CLIENT_SSL              2048    /* Switch to SSL after handshake */
#define CLIENT_IGNORE_SIGPIPE   4096    /* IGNORE sigpipes */
#define CLIENT_TRANSACTIONS 8192    /* Client knows about transactions */
#define CLIENT_RESERVED         16384   /* Old flag for 4.1 protocol  */
#define CLIENT_SECURE_CONNECTION 32768  /* New 4.1 authentication */
#define CLIENT_MULTI_STATEMENTS (1UL << 16) /* Enable/disable multi-stmt support */
#define CLIENT_MULTI_RESULTS    (1UL << 17) /* Enable/disable multi-results */

 

其中CLIENT_NO_SCHEMA 位一旦被置，则不允许schema.table形式的请求，会报“Database not selecte"