SQL Server Update usage

Update is one of our common SQL statements. Update is mainly used to change the existing data in the table.

Update a table: Update product set l_parentid = '1'

Detailed Description: Update table name set column name = parameter

Update two or more tables: Update product set l_parentid = producttype. parentid from product, producttype where product. l_typeid = producttype. ID

Detailed Description: Update table name set column name = parameter from table name 1, table name 2 where specified condition

 

UPDATEDetailed syntax
{
table_name WITH ( < table_hint_limited > [ ...n ] )
| view_name
| rowset_function_limited
}
SET
{ column_name = { expression| Default | null}
| @variable = expression
| @variable = column = expression } [ ,...n ]

{ { [ FROM { < table_source > } [ ,...n]

[ WHERE
< search_condition > ] }
|
[ WHERE CURRENT OF
{ { [ GLOBAL ] cursor_name} |cursor_variable_name }
]}
[ OPTION ( < query_hint > [ ,...n ] ) ]

< table_source > ::=
table_name [ [ AS ] table_alias ] [ WITH ( < table_hint > [ ,...n ] ) ]
    | view_name [ [ AS ] table_alias ]
| rowset_function [ [ AS ] table_alias ]
| derived_table [ AS ] table_alias [ ( column_alias [ ,...n ] ) ]
| < joined_table >

< joined_table > ::=
< table_source > < join_type > < table_source > ON < search_condition >
| < table_source > CROSS JOIN < table_source >
| < joined_table >

< join_type > ::=
[ INNER | { { LEFT | RIGHT | FULL } [OUTER] } ]
[ < join_hint > ]
JOIN

< table_hint_limited > ::=
{FASTFIRSTROW
| HOLDLOCK
| PAGLOCK
| READCOMMITTED
| REPEATABLEREAD
| ROWLOCK
| SERIALIZABLE
| TABLOCK
| TABLOCKX
| UPDLOCK
}

< table_hint > ::=
{INDEX ( index_val [ ,...n ] )
| FASTFIRSTROW
| HOLDLOCK
| NOLOCK
| PAGLOCK
| READCOMMITTED
| READPAST
| READUNCOMMITTED
| REPEATABLEREAD
| ROWLOCK
| SERIALIZABLE
| TABLOCK
| TABLOCKX
| UPDLOCK
}

< query_hint > ::=
{{ HASH | ORDER } GROUP
| { CONCAT | HASH | MERGE } UNION
| {LOOP | MERGE | HASH } JOIN
| FAST number_rows
| FORCE ORDER
| MAXDOP
| ROBUST PLAN
| KEEP PLAN
}

 

Parameters

Table_name

The name of the table to be updated. If the table is not on the current server or database or is not owned by the current user, the name can be specified by the linked server, database, and owner name.

Set

Specifies the list of columns or variable names to update.

TIPS: SQL Server online series provides a detailed reference for Transact-SQL.

Before using update, please back up the data. When the data used is updated incorrectly, you will be suspended.