SQL MySQL is present on update, and there is no notation for inserting (go)

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Sqlsever data exists on the update, there is no insertion of two methods

Two ways to use it frequently:

1. Update, if @ @ROWCOUNT = 0 Then insert

UPDATETable1 SETColumn1 = @newValue Whereid = @id

[email protected] @ROWCOUNT = 0

BEGIN

INSERT INTOTable1 (Id, Column1) VALUES (@id, @newValue)

END

If a row of data exists for the update to be valid, the insert will be executed. Personal feelings This approach tends to be the case where data is mostly present in the data table;

2. If row exists update, otherwise insert

Ifexists (select* FROMTable1 whereid = @id)

BEGIN

UPDATETable1 SETColumn1 = @newValue Whereid = @id

END

ELSE

BEGIN

INSERT INTOTable1 (Id, Column1) VALUES (@id, @newValue)

END

In this method, the SELECT statement executes immediately after execution of update or insert, and consumes less resources than method one.

3.mysql data exists on update, does not exist on insert

Insert into T (F1,F2,F3) VALUES (v1,v2,v3) on DUPLICATE KEY UPDATE v3=values (v3) +v3

SQL MySQL is present on update, and there is no notation for inserting (go)