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How to modify table contents in sql

清浅

May 14, 2019 am 09:50 AM

sql

SQL method to modify table contents: You can modify it by executing the [update table name set column name 1=value, column name 2=value where condition;] command. Use this command to modify a row, a single column or multiple columns of data in a single table.

How to modify table contents in sql

There are three ways to modify the content of a table in sql: using SSMS database management tools to modify the content, using T-SQL scripts to modify the content and multiple tables Association changes the content in the table, etc.

(Recommended tutorial: mysql video tutorial)

Use SSMS database management tool to modify data

Modify any one or more All are OK

1: Open the database, select the data table, right-click -> Edit all rows (if not configured, click to edit the first 200 rows).

How to modify table contents in sql

#2. Edit the data that needs to be modified - "After the editing is completed, right-click on the blank space -" Select Execute SQL to edit successfully.

How to modify table contents in sql

Use T-SQL script to modify data

Modify one row, single column or multiple columns of data in a single table

Syntax: update table name set column name 1 = value, column name 2 = value where condition;

Example 1:

update test1  set age=&#39;21&#39; where id=&#39;1&#39;;

Example result:

How to modify table contents in sql

Modify multiple rows, one column or multiple columns of data in a single table

Syntax: update top(quantity) table name set column name 1=value, column name 2=value 2 where Condition;

Example:

update test1 set age=&#39;23&#39; where id in (&#39;1&#39;,&#39;2&#39;);
update test1 set age=&#39;22&#39; where id between &#39;3&#39; and &#39;4&#39;;
update test1 set age=&#39;23&#39; where id>=&#39;5&#39; and id <=&#39;6&#39;;
update top(2) test1 set age=&#39;23&#39; where id>=&#39;5&#39;;
update test1 set age=&#39;23&#39; where test1.id in (select top(2) id from test1 order by id desc);

Example result:

How to modify table contents in sql

##Multiple table association Modify the data in the table

Syntax: update table 1 set table 1. column 1 = value, table 1. column 2 = value from table 1 as a, table 2 as b where a. column name = b. Column name;

Example:

update test1 set test1.name=&#39;李华&#39;,test1.sex=&#39;女&#39; from test1 as a,test2 as b where a.classid=b.id;

Example result:

How to modify table contents in sql

Summary: Modification Data table data, flexible combination and modification of data columns, data sources, and query conditions are the key.

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