CREATE TABLE #a(f1 VARCHAR(30),    f2 VARCHAR(40) )

 CREATE TABLE #b(f1 VARCHAR(30),    f2 VARCHAR(40) )

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 INSERT INTO #a(f1,f2)VALUES('','a1')

 INSERT INTO #a(f1,f2)VALUES('','a2')

 INSERT INTO #a(f1,f2)VALUES('','a3')

 INSERT INTO #a(f1,f2)VALUES('','a4')

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

 INSERT INTO #b(f1,f2)VaLUES('','b1')

 INSERT INTO #b(f1,f2)VaLUES('','b2')

 --INSERT INTO #b(f1,f2)VALUES('3','b3')

 --INSERT INTO #b(f1,f2)VaLUES('4','b4')

 SELECT a.*,b.*

 FROM #a AS a LEFT JOIN #b AS b ON a.f1 = b.f1

 --

 SELECT a.*,b.*

 FROM #a AS a LEFT OUTER JOIN #b AS b ON a.f1 = b.f1

 -----------

 SELECT a.*,b.*

 FROM #a AS a , #b AS b WHERE  a.f1 = b.f1

 --

 SELECT a.*,b.*

 FROM #a AS a INNER JOIN #b AS b ON a.f1 = b.f1