sqlserverupdate
详细⽤法
UPDATE
是我们常
SQL
语句之⼀
,update
主要⽤于更改表中的现有数据
.
更新⼀个表
:update product set l_parentid ='1'
详细解说
: update
表名
set
列名
=
参数
更新两个表或多个表
: update product set l_parentid = producttype.parentid from product,producttype where product.l_typeid =producttype.id
详细解说
: update
表名
set
列名
=
参数
from
表名
1,
表名
2 where
指定条件
UPDATE
详细语法
{
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