oracle SQL解析步骤小结
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2023-12-05 08:11:28
1 the syntax of the sql statement is verified. sql的语法检查 2 the data dictionary is searc...
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
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