How to insert Distinct Records from Table A to Table B (both tables have same structure)
I want to insert only Distinct Records from Table "A" to Table "B". Assume both the tables has sa开发者_JS百科me structure.
If by DISTINCT
you mean unique records that are on TableB that aren't already in TableA, then do the following:
INSERT INTO TableB(Col1, Col2, Col3, ... , Coln)
SELECT DISTINCT A.Col1, A.Col2, A.Col3, ... , A.Coln
FROM TableA A
LEFT JOIN TableB B
ON A.KeyOfTableA = B.KeyOfTableB
WHERE B.KeyOfTableB IS NULL
INSERT INTO B SELECT DISTINCT * FROM A
You might not want the id column of the table to be part of the distinct check, so use this solution if that's the case: https://stackoverflow.com/a/5171345/453673
INSERT INTO TableB
(Col1, Col2, ...)
SELECT DISTINCT Col1, Col2, ...
FROM TableA
INSERT INTO TableB
SELECT *
FROM TableA AS A
WHERE NOT EXISTS(SELECT * FROM TableB AS B WHERE B.Field1 = A.Field1)
-- If need: B.Field2 = A.Field2 and B.Field3 = A.Field3
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