1、schema。 pg中的schema表示当前db中数据库对象的命名空间(namespace),数据库对象包括但不限于表、函数、视图、索引等。 对于熟悉mysql的人来说,在第一次看到pg中的schema的概念时,可能会疑惑,schema不是表示database的吗? 注:mysql中schema和database是一个概念。create database 和create schema的效果是相同的...
In [4]: t.create(bind=engine) 1. 2. 3. 4. 5. 6. 7. 8. example 2:表删除 有2种方式,其一: In [5]: t.drop(bind=engine,checkfirst=True) 另一种是: In [5]: metadata.drop_all(bind=engine,checkfirst=True),其中可以借助tables属性指定要删除的对象 1. 2. 3. 4. example 3: 5种...
This method runs the script from the drop_tables.sql file, generating the DROP TABLE statements and executing them to delete all tables in the specified database. Using this method, you can DELETE ALL the tables in any MySQL database by simply changing the database name in your SQL file. ...
2. 获取/释放全局锁 -- 获取全局只读锁,所有写操作被阻塞FLUSH TABLESWITHREAD LOCK;-- 释放全局锁UNLOCK TABLES; 注意:一旦执行全局锁,所有 schema 下的表都进入只读,慎用于线上高并发环境! 二、表锁(Table Lock) 1. 原理与分类 作用域:锁定单张表 MyISAM引擎:默认使用表锁;InnoDB在显式LOCK TABLES时可使...
TRADITIONAL ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER, NO_ZERO_DATE, NO_ZERO_IN_DATE, STRICT_ALL_TABLES, STRICT_TRANS_TABLES 之所以称之为TRADITIONAL模式,是因为它启用这样的模式——它们使得MySQL在处理输入值时,可以表现得像那些会拒绝无效数据的传统数据库一样。它有点像严格模式,但是对于更加严格...
UPDATE performance_schema.setup_instruments SET ENABLED= 'YES' WHERE NAME = 'statement/sql/show_databases'; UPDATE performance_schema.setup_instruments SET ENABLED= 'YES' WHERE NAME = 'statement/sql/show_tables'; UPDATE performance_schema.setup_instruments SET ENABLED= 'YES' WHERE NAME = 'stateme...
(不会setnames 、忽略key、添加锁)减小了生成文件的体积-d:备份表结构-t :备份表内容-F:刷新切割binlog日志(分段备份导入)--master-data :增加binlog日志文件名及对应的位置点;#注意需要开启log_binON|查看-e"show variables;"|grep log_bin-x :锁定所有表 #--lock-all-tables-l :锁定指定表--single-...
I have a schema where I want all my tables to be encrypted. When creating the schema, a default encryption attribute can be set. All tables that are created in the schema will then inherit this schema default encryption setting. Looking at the figure above, if encryption is configured for ...
#添加表级S锁 LOCK TABLES t READ; #添加表级X锁 LOCK TABLES t WRITE; #查看表上加过的锁 SHOW OPEN TABLES; 或 SHOW OPEN TABLES WHERE IN_USE>0; #释放锁 UNLOCK TABLES;表级锁S/X锁的兼容情况如下, 意向锁(Intention Lock)平时在添加行级锁的时候,InnoDB引擎会自动帮我们维护相应的IS或IX两种表...
The TABLES table provides information about tables in databases. The TABLES table has these columns: TABLE_CATALOG The name of the catalog to which the table belongs. This value is always def. TABLE_SCHEMA The name of the schema (database) to which the table belongs. TABLE_NAME Th...