delete duplicate records in sql

SQL Delete duplicate dataThis article provides a MySQL delete duplicate data, is the data table there are more than two duplicate data, delete the smallest number of a piece of informat

Label:Mesh: Zdjz_dis The NAME field has a duplicate value, delete the duplicate value deleted * from zdjz_dis WHERE name in (select Name from Zdjz_dis GROUP by NAME has count (NAME) >1); The above procedure will remove all the same values, including the one you want, and delete the

How can I use an SQL statement to delete the same records in a table? Delete duplicate data I. Primary KeyA. Unique field ID (unique primary key)Delete tableWhere id not in(Select max (ID) from Table group by col1, col2, col3...)

Tags: play statement span IDE pen proc Height GROUP by view1: Delete duplicate data --First step: Find duplicate Data firstSelectProcinstid fromRecord_errorlog GROUP BY Procinstid have Count (Procinstid)>1--Take a lookSelect* fromRecord_errorlogwhereProcinstidinch(SelectProcinstid fromRecord_errorlog GROUP BY Procinstid have Count (Procinstid)>1); --The second p

Tags: style http color using data for AR DivSQL statement method to delete all records in a tableHow to delete all the records in a table with an SQL statement, share my method here.Reference Links: How do SQL statements

Write a SQL query to delete all duplicate e-mail entries in a table named Person , keeping unique emails based on its smallest Id. +----+------------------+| Id | Email |+----+------------------+| 1 | [Email protected] | | 2 | [email protected] | | 3 | [Email protected] |+----+------------------+id is the primary key, column for th

to judge repetition. For example, if only col1 is used, if the content of col1 is the same, the record is the same. 5.Copy codeThe Code is as follows: select identity (int, 1, 1) as id, * into # temp from tabelSelect * from # temp where id in (Select max (id) from # emp where having count (*)> 1 group by col1, col2, col3 ...) 6.Copy codeThe Code is as follows: select distinct * into # temp from tablenameDelete tablenameGoInsert tablename select * from # temp SqlclubGoDrop table # temp The prece

CREATE TABLE TMP as SELECT ID from Get_review_url WHERE (no,title,name,content) in (SELECT no,title,name,content from Get_review_url GROUP by No,title,name,content have COUNT (*) > 1) and ID not in (SELECT MIN (ID) from Get_review_url GR OUP by No,title,name,content have COUNT (*) >1);D elete from Get_review_url WHERE ID in (SELECT ID from tmp);D ROP TABLE tmpCopyright notice: This article blog original article. Blogs, without consent, may not be reproduced.MySQL

Mysql-> SQL statement: An SQL statement is used to delete duplicate data in the table. Occasionally, when I talked to my colleagues about this issue, I wrote the code for your reference ~ // Data preparation Mysql code drop table t_user; create table t_user (id int (5) not null auto_increment, username varchar (10), ag

for such a resultID Name Value1 a pp3 B III4 B pp6 C pp8 C IIIMethod 1Delete yourtablewhere [id] not in (Select MAX ([id]) from yourtableGroup BY (name + value))Method 2Delete aFrom Table a LEFT join (Select Id=min (ID) from table GROUP by Name,value) B on A.id=b.idwhere b.id is nullSQL statement for querying and deleting duplicate records 1, find redundant duplicate