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Join Date: Nov 2007
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Junior Poster
hi
I want to fetch data from four tables using a single query.please tell me how to do that.
thanks in advance
I want to fetch data from four tables using a single query.please tell me how to do that.
thanks in advance
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Join Date: Apr 2008
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Posting Whiz in Training
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Originally Posted by lydia21 
hi
I want to fetch data from four tables using a single query.please tell me how to do that.
thanks in advance
try select * from a, b, c, d
then sort out at your leisure
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Join Date: Jun 2008
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Light Poster
sql Syntax (Toggle Plain Text)
change table names and column names accordingly
Last edited by peter_budo : Jun 14th, 2008 at 1:44 pm. Reason: Keep It Organized - please use [code] tags
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Join Date: Jun 2008
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Light Poster
put your create table syntax for all 4 tables
then some 1 can send a exact query
then some 1 can send a exact query
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Join Date: Apr 2008
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Posting Whiz in Training
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Originally Posted by varmadba
put your create table syntax for all 4 tables
then some 1 can send a exact query
Obviously a task too overcharging him. Why not letting him doing plain cross products first a la posting #2 ?
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Join Date: Jun 2008
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select * from a, b, c, d
this will produce a Cartesian output
say you have 100 rows in each table
o/p will be 100 x 100 x 100 x 100
you know why it doesn't have how to join tables
this will produce a Cartesian output
say you have 100 rows in each table
o/p will be 100 x 100 x 100 x 100
you know why it doesn't have how to join tables
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Join Date: Apr 2008
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Posting Whiz in Training
correct, it is cartesian product, not cross product. thank you, varmadba 
True, the cardinality is just the total product of the cardinalities of all involved tables. But this might be ok to him. So he would learn how to figure out the essential rows manually doing true handiwork.
True, the cardinality is just the total product of the cardinalities of all involved tables. But this might be ok to him. So he would learn how to figure out the essential rows manually doing true handiwork.
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