[Solved] How do I compare two columns in the same table?
I would like to compare two columns in the same table. I want to be able to return all rows where the two columns have the same value.
I am looking for something like SELECT * FROM FOO WHERE C1 = C4.
Therefore in the example below I would return only the first row:
C1 || C2 || C3 || C4
--------------------------
1 || a || b || 1
2 || a || b || 4
3 || b || d || 2
4 || b || d || 2
If it matters, I am using SQLite (more specifically WebSQL).
Solution #1:
SELECT * FROM FOO WHERE C1 = C4 should work. Does it not?
If not, are they the same data type and length? You may need to convert.
I don’t know about WebSql, but I’ve seen some db systems that refuse to match if one is a varchar(5) and the other is a varchar(10) even though they hold the same value.
In those systems you have to use something like
Convert(varchar, 10, FieldName)
to get a match.
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