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Joining tables

SELECT b.name, b.ra, b.dec, b.mag bmag, r.mag rmag

FROM bsources b, rsources r

WHERE b.name = r.name;

result:

•

NAME RA DEC BMAG RMAG

---------- ---------- ---------- ---------- ----------

NGC1234 12.34 45.67 17.3 19.3

•NGC4321 23.45 56.78 18.2 17.2


	Only joins rows for which name does not contain the NULL value!!!
	FROM a, b means the cartesian product of a and b (m rows in a, n rows in b means m*n rows for the cartesian product!)
	Explain use of aliases for tables?