how to add new column in ms access table with this criteria
i have two msaccess tables
tableA
textA nu开发者_如何转开发mA
bd 1
as 0
aa 2
cc 4
tableB
textB
ss
aa
bd
as
how to write an sql query to add one column called numB in table B so that final table B would be
tableB ( basically fetching values from tableA )
textB numB
ss 0 ( because ss is not there in table A )
aa 2
bd 1
as 0
This SQL will make a new table called tblFooC
SELECT tblFooB.TextB, nz([NumA],0) AS Expr1 INTO tblFooC
FROM tblFooB LEFT JOIN tblFooA ON tblFooB.TextB = tblFooA.TextA;
You could then delete table tblFooB and rename tblFooC to tblFooB
You cannot do this in one query. You can create TableC from tables A & B and then rename and/or delete so that table C becomes table B, or you can run a DDL query to add a column to Table B. I suggest the second option.
To add a column:
ALTER TABLE TableB ADD COLUMN NumB Integer
To update:
UPDATE TableA
RIGHT JOIN TableB ON TableA.TextA = Tableb.TextB
SET TableB.BumB = Nz([NumA],0);
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