数据库脚本

1、查询执行最慢的sql

select *
 from (select sa.SQL_TEXT,
        sa.SQL_FULLTEXT,
        sa.EXECUTIONS "执行次数",
        round(sa.ELAPSED_TIME / 1000000, 2) "总执行时间",
        round(sa.ELAPSED_TIME / 1000000 / sa.EXECUTIONS, 2) "平均执行时间",
        sa.COMMAND_TYPE,
        sa.PARSING_USER_ID "用户ID",
        u.username "用户名",
        sa.HASH_VALUE
     from v$sqlarea sa
     left join all_users u
      on sa.PARSING_USER_ID = u.user_id
     where sa.EXECUTIONS > 0
     order by (sa.ELAPSED_TIME / sa.EXECUTIONS) desc)
 where rownum <= 50;

2、查询次数最多的sql

select *
 from (select s.SQL_TEXT,
        s.EXECUTIONS "执行次数",
        s.PARSING_USER_ID "用户名",
        rank() over(order by EXECUTIONS desc) EXEC_RANK
     from v$sql s
     left join all_users u
      on u.USER_ID = s.PARSING_USER_ID) t
 where exec_rank <= 100;

3、数据更新时间

Select scn_to_timestamp(ora_rowscn),TTRD_TRADE_CLOSE_DETAIL.* from TTRD_TRADE_CLOSE_DETAIL where tsk_id = '1178986'

4、查询锁表用户

 select sess.sid, sess.MACHINE,
   sess.serial#, 
   lo.oracle_username, 
   lo.os_user_name, 
   ao.object_name, 
   lo.locked_mode 
from v$locked_object lo, 
   dba_objects ao, 
   v$session sess 
where ao.object_id = lo.object_id and lo.session_id = sess.sid;

5、查询表中是否存在某个字段

DELIMITER $$
CREATE PROCEDURE ALTER_TABLE_ADD_COLUMN() BEGIN -- 创建存储过程
	IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='表名' AND TABLE_SCHEMA='库名' AND COLUMN_NAME='查询字段') THEN -- 判断字段是否存在
		ALTER TABLE 库名.表名 ADD 字段名 int(11) DEFAULT 0; -- 添加字段
	END IF;
END $$
DELIMITER;
CALL ALTER_TABLE_ADD_COLUMN(); -- 调用存储过程
DROP PROCEDURE ALTER_TABLE_ADD_COLUMN; -- 删除存储过程

6、批量插入数据

oracle

#Oracle 批量插入
INSERT ALL 
INTO mytable (column1,column2,column3,...) VALUES (value1,value2,value3,...)
INTO mytable (column1,column2,column3,...) VALUES (value1,value2,value3,...)
INTO mytable (column1,column2,column3,...) VALUES (value1,value2,value3,...)
SELECT * FROM dual;
commit;

mysql

INSERT INTO mytable (column1,column2,column3,...) -- 表都可以shenglue
VALUES (value1,value2,value3,...),
(value1,value2,value3,...),
(value1,value2,value3,...);