CODEWITHSUNDEEP
mysqlsqloracle-database
psylocybe
psylocybe

Reputation: 23

update multiple rows with SQL

I have two tables

student:
(student_id, student_name)

and

license:
(license_id, student_id)

And I have a list of student ids (for example "3,4,5")

I want to update 3(list size) rows in table license and change their student_id field from null to 3,4,5 respectively.

How do I do that? Running a loop of updates is not a suitable solution for me. Thanks in advance.

Upvotes: 1

Views: 249

Answers (1)

Allan Chua
Allan Chua

Reputation: 10175

I have an MS SQL version of an id parser. You can use this to generate a table with a single column that contains your ids it takes a parameter of type varchar(max). you can use it on a select statement like 

SELECT * FROM TABLENAME
WHERE COLUMNAME IN (SELECT value FROM parseIDs ('1,2,3'))

Here is the function:

CREATE FUNCTION parseIDs  
(
    @IDList VARCHAR(MAX)
)
RETURNS @IDs TABLE (value VARCHAR(80))
AS
BEGIN
    IF @IDList is null
        RETURN

    DECLARE @Len INT, 
            @Pos INT, 
            @Cur INT

    SELECT @Pos = 0, 
           @Len = 0, 
           @Cur = 1, 
           @IDList =  CASE 
                        WHEN SUBSTRING(@IDList, LEN(@IDList), 1) = ',' THEN @IDList 
                        ELSE @IDList + ',' 
                      END

    SELECT @Pos = CHARINDEX( ',', @IDList, @Cur)
    WHILE (@Pos <> 0)
    BEGIN
        INSERT @IDs VALUES (LTRIM(SUBSTRING( @IDList, @Cur, (@Pos - @Cur))))
        SELECT @Cur = @Pos + 1
        SELECT @Pos = CHARINDEX( ',', @IDList, @Cur)
    END
    return
END

Upvotes: 1

Related Questions