Now we have realized that custid 1, 4 & 5 are duplicate. The self-join statement accompanied by delete statement will give us the desired output of keeping the last duplicate record by eliminating all the previous duplicate records. We will use theCommon Table Expression (CTE)and put the Sel...
How to Delete Duplicate Records in SQL Server Usually on daily basis we usually need to perform removing duplicate records from a table. This post can help you to understand “How to Delete Duplicate Records in SQL Server”. Here consider an example for removing duplicate records. IF EXISTS(SE...
如果insert 的事务出现了duplicate-key error ,事务会对duplicate index record的记录加共享锁。这个共享锁在并发的情况下是会产生死锁的,比如有两个并发的insert都对要对同一条记录加共享锁,而此时这条记录又被其他事务加上了排它锁,排它锁的事务将这条记录删除后,两个并发的insert操作会发生死锁。 delete? delet...
To do this, you must first decide which rows you want to keep. For example, you might want to preserve the oldest row. To do this you'll needanother column in the table(e.g. insert date, id, etc.) that is not one of the copied values. Assuming you have this, there are two wa...
for_delete; Query OK, 3 rows affected (0.04 sec) mysql> insert for_delete (name) values ('D'); Query OK, 1 row affected (0.02 sec) mysql> select * from for_delete; +---+---+ | id | name | +---+---+ | 4 | D | +---+---+ 1 row in set (0.00 sec)截断表 trunca...
Delete Command in SQL Server The simplest syntax of the statement is as follows: Delete FROM <TableName> WHERE <Condition> You need to provide the table name and the criteria/condition for the data (rows) deletion from the table. Note: It is crucial to use the DELETE statement with a co...
#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'table AS bevinco_2005_master LEFT JOIN table AS bevinco_2005_master2 ON bevinc' at line 2 ...
INSERT<target>FROMTABLE<itab> [ACCEPTING DUPLICATE KEYS] 插入数据时,避免有相同主键引起dump error错误,使用ACCEPTING DUPLICATE。此时sy-subrc返回4. 三、UPDATE 一条数据 UPDATE<target>FROM<wa>."表结构相同 多条数据. UPDATE<target>FROMTABLE<itab>.UPDATE<target>SET<set1> <set2>WHERE<cond>. ...
开始我们拿sql到数据库查询平台查库执行计划,无奈这个平台有bug,delete语句无法查看,所以我们改成select,“应该”是一样。这个“应该”加了双引号,导致我们走了一点弯路。 EXPLAIN SELECT * from t_table_1 where task_id in (select id from t_table_2 where uid = 1) ...
FROM tbl_RemoveDuplicate) AS T WHERE T.RowNumber > 1); Check the result: 1 2 3 4 5 6 7 8 9 SELECT *FROM tbl_RemoveDuplicate; id | name ---+--- 1 | ABC 2 | XYZ 4 | RFQ 5 | PQR 6 | EFG (5 rows)SQL Puzzle: SQL Advance Query - Find the Order basis on thier Statu...