oracle SQL解析步骤小结

数据库  /  管理员 发布于 6年前   151

1 The syntax of the SQL statement is verified.

SQL的语法检查

2 The data dictionary is searched to verify table and column definitions.

从数据字典检查表名和字段名

3 The data dictionary is searched to verify security privileges on relevant objects.

从数据字典中检查权限

4 Parse locks are acquired on the relevant objects.

解析相关对象的锁

5 The optimal execution plan is determined.

选在执行计划运行SQL

6 The statement is loaded into the shared SQL area (also known as the library cache) in the shared pool of the system global area (SGA).

执行后SQL语句放在SGA的SQL共享区