How to use Update to realize multi-table joint update in SQL
This article will explain in detail how to use Update to achieve multi-table joint update in SQL, the content of the article is of high quality, so the editor will share it with you for reference. I hope you will have a certain understanding of the relevant knowledge after reading this article.
(1) sqlite multi-table update method
The copy code is as follows:
/ /--
Update t1 set col1=t2.col1
From table1 t1
Inner join table2 t2 on t1.col2=t2.col2
This is a very simple batch update statement that supports this syntax in SqlServer but not in sqlite
Sqlite can be converted to the following syntax
The copy code is as follows:
Update table1 set col1= (select col1 from table2 where col2=table1.col2)
Update ta_jbnt_tzhd_pht_Area_xiang set T1 = (select sys_xzqhdm.name from sys_xzqhdm
Where t2=sys_xzqhdm.code)
(2) SQL Server multi-table update method
The copy code is as follows:
/ /--
SQL Server syntax: UPDATE {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])]
SQL Server example:
The copy code is as follows:
Update a set a.gqdltkscompilb.gqdltksMagnetica.bztkscompilb.bztks from
Landleveldata a,gdqlpj b where a.GEO_Code=b.lxqdm
Update method of multiple tables in access Database
The copy code is as follows:
X = "update" + DLTB + "an inner join tbarea2 b on a.objectid=b.FID set a." + fd_dltb_xzdwmj + "= b.area_xzdw, a." + fd_dltb_lxdwmj + "= b.area_lxdw"
SQLList.Add (x)
(3) Oracle multi-table update method
Oracle syntax:
The copy code is as follows:
UPDATE updatedtable SET (col_name1 [, col_name2...]) = (SELECT
Col_name1, [, col_name2...] FROM srctable [WHERE where_definition])
Oracel example:
The copy code is as follows:
Update landleveldata a set (a.gqdltks, a.bztks) = (select b.gqdltks
B.bztks from gdqlpj b where a.GEO_Code=b.lxqdm)
(4) MySQL multi-table update method
MySQL syntax:
The copy code is as follows:
UPDATE table_references SET col_name1=expr1 [, col_name2=expr2...]
[WHERE where_definition]
MySQL example:
The copy code is as follows:
Update landleveldata a, gdqlpj b set a.gqdltks = b.gqdltks, a.bztks=
B.bztks where a.GEO_Code=b.lxqdm
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