40100 WITH CONSISTENT SNAPSHOT */,那么会话2这两条记录是都看不到的,效果就像是从会话一开始就自动执行了select * from backup。这样就保证了整个备份期间数据都是一致的。 备份表可以执行的语句: 备份库当中所有表都可以并发的执行DML和查询语句(SELECT)。但是DDL有一些特殊。 从上面的通用日志中可以看出,在刚...
dynstr_append_checked(&query_string, "SELECT /*!40001 SQL_NO_CACHE */ * FROM "); dynstr_append_checked(&query_string, result_table); // 改为使用 mywhere // if (where) // { // freemem= FALSE; // text= fix_identifier_with_newline(where, &freemem); // print_comment(md_result...
Theinitialsizeofthe bufferforclient/server communication.Whencreating multiple-rowINSERTstatements (aswiththe--extended-insert or --opt option), mysqldump creates rows up to net_buffer_length bytes long. If you increase this variable, ensure that the MySQL server net_buffer_length system variable has...
// 创建savepoint if (opt_single_transaction && mysql_get_server_version(mysql) >= 50500) { verbose_msg("-- Setting savepoint...\n"); if (mysql_query_with_error_report(mysql, 0, "SAVEPOINT sp")) return 1; } while ((table = getTableName(0))) { char *end = my_stpcpy(afterdot,...
添加–q(--quick) 参数时,select出来的结果将不会存放在缓存中,而是直接导出到标准输出中。如果不添加该参数,则会把select的结果放在本地缓存中,然后再输出给客户端。 导出表时默认会加锁,必须运行中的数据库进行备份请添加 --skip-opt选项 --single-transaction 一致性备份 ...
4 Query select @@collation_database 4 Query SHOW TRIGGERS LIKE 'user' 4 Query SET SESSION character_set_results = 'utf8' 4 Quit 它的实现使用了 FLUSH TABLES; FLUSH TABLES WITH READ LOCK; 语句。在最后没有看到解锁语句。 它请求发起一个全局的读锁,会阻止对所有表的写入操作,以此来确保数据的一...
(`id`,`title`,`bit_default`,`time_span`,`recommend_cate`,`weighting`,`user_id`,`recommend_by`); Query OK, 1 row affected (0.02 sec) Records: 1 Deleted: 0 Skipped: 0 Warnings: 0 mysql> select * from object_justwinit_video\G; *** 1. row *** id: 1 uuid: NULL title: 2 ...
FLUSH TABLES WITH READ LOCK 。 ... 备份表可以执行的语句: 整个实例变成了只读,所有表的DDL和DML都会被阻塞,只能执行查询语句(SELECT)。 情况三,使用single-transaction mysqldump - h127 . 0.0 . 1 - uwxp - p 'wxp' -- single - transaction test > dump . sql ...
40100 WITH CONSISTENT SNAPSHOT */2023-07-11T16:15:50.938678+08:002692QuerySHOWVARIABLESLIKE'gtid\_mode'2023-07-11T16:15:50.980335+08:002692QuerySELECT@@GLOBAL.GTID_EXECUTED2023-07-11T16:15:50.980566+08:002692QuerySHOWMASTERSTATUS2023-07-11T16:15:50.980758+08:002692QueryUNLOCKTABLES...略2023-07...
2023-05-06T16:49:07.658863+08:00 15 Query SELECT LOGFILE_GROUP_NAME, FILE_NAME, TOTAL_EXTENTS, INITIAL_SIZE, ENGINE, EXTRA FROM INFORMATION_SCHEMA.FILES WHERE FILE_TYPE = 'UNDO LOG' AND FILE_NAME IS NOT NULL AND LOGFILE_GROUP_NAME IS NOT NULL GROUP BY LOGFILE_GROUP_NAME, FILE_NAME, ...