Why Do you need it? To refer to fields within the same table you can go for self-join. Below is the example SQL query for self-join.
Self-Join SQL Query
Let us first create two copies of the same table MATCH, M1 and M2:
CREATE TABLE M1 AS SELECT * FROM MATCH;
CREATE TABLE M2 AS SELECT * FROM MATCH;
Then, we could join M1 and M2:
SELECT M1.PAPER FROM M1, M2 WHERE M1.PAPER = M2.PAPER AND M1.CODE = 601 AND M2.CODE = 602;
The self-join allows us to perform this sort of operation without actually having to copy the table. We can just act as if we had two copies.
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