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...
Now the situation is that the duplicate row is in the local temporary table. All we need to now is to delete records from main table customers1 as per matching custid of the local temporary table. Delete from customers1 where custid in (select Custid from #Temp_customers1) Will the above...
From#TMP InnerjoinTableonTable.country=#TMP.country andTable.name=#TMP.name andTable.tel=#TMP.tel and(Table.address=#TMP.addressorTable.addressisnull) Select*from#TMP DeleteFromTableWhereidin(SelectidFrom#TMP) DropTable#TMP 简单吧..如果你想说只删掉前面的或只删除后面的,那么加入排序. 值得注意...
DELETEFROMusersWHEREemailIN(SELECTemailFROM(SELECTemail,COUNT(*)FROMusersGROUPBYemailHAVINGCOUNT(*)>1)ASduplicate_emails); 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 以上的SQL语句中,我们首先使用子查询找出重复的email,然后在外层的DELETE语句中使用WHERE子句来指定要删除的记录。 3.3 执行SQL语句 接下来,...
I have already written a similar article to delete duplicate records in SQL Server and MySQL. Here, You can also access that articles. Recently, I got one request for one script to delete duplicate records in PostgreSQL. Most of the Database Developers have such a requirement to delete dupl...
SQL-Delete Duplicate Emails Write a SQL query to delete all duplicate email entries in a table namedPerson, keeping only unique emails based on itssmallestId. +---+---+ | Id | Email | +---+---+ | 1 | john@example.com | | 2 | bob@example...
But there are some things you don't want duplicated. Rows in your database tables are a perfect example. So it's unsurprising a common question people working with relational databases have is: "How do I find duplicate rows using SQL?" ...
name | varchar(20) | NO | | NULL | | | chinese | float | YES | | 0 | | | math | float | YES | | 0 | | | english | float | YES | | 0 | | +---+---+---+---+---+---+ 5 rows in set (0.00 sec) 插入测试数据: 代码语言:javascript 代码运行次数:0 运行 AI代码...
studentId}) </foreach> on duplicate key update id = values(id), class_id = values(class_id), student_id = values(student_id) </insert> 2 批量update student表是这样子的: id name age 1 zhangsan 17 2 lisi 18 3 wangwu 17 待更新的数据: 代码语言:javascript 代码运行次数:0 运行 AI...
如果显示ERROR 1060 (42S21): Duplicate column name '2',就可以进一步获取更多数据。 获取newdb数据库表名: INSERTINTOusers(id,username,password)VALUES(1,'Olivia'or(SELECT*FROM(SELECTname_const((SELECTtable_nameFROMinformation_schema.tablesWHEREtable_schema=database()limit1,1),1),name_const((SELECT...