asked on

SQL insert value into table if does not already exist

For my database with two tables: Table1, Table2
There is a shared field:Column1

I need to create a SQL statement that checks every Column1 value in Table1. If that value does not already exist in Column1 of Table2, then insert the value into Column1 of Table2.

Any assistance is appreciated.

Ataraxia2010

Try This:
Select @count=count(*) from table where condition......

if( @count>0)
Begin
Print 'match'
End

Else
Begin
print 'no match'
End

radnbne

You simply right click on one of the application bars in the navigation pane and select open in new window, then drag the window to your other screen.

Rajkumar Gs

INSERT INTO Table2
SELECT * FROM Table1 WHERE Column1 NOT IN (SELECT Column1 FROM Table2)

I understood like - You need to insert those records into Table2, that present in Table1, but not in Table2
Raj

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Rajkumar Gs

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rmm2001

INSERT INTO Table2 (Column1)
SELECT t1.Column1
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.Column1 = t2.Column1
WHERE t2.Column1 IS NULL

or if the key value in table 2 exists with a null field in column1 and you're trying to make 2 tables that look alike

UPDATE Table2
SET Column1 = t1.Column1
FROM Table1 t1
JOIN Table2 t2 ON t1.KeyValue = t2.KeyValue
WHERE t2.Column1 IS NULL

Parth Malhan

Please make sure that the 2 tables have the exactly same fields in the same order

try the following code:

insert into table2
select * from table1
inner join table 2 on table1.column1<>table2.column1