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Foreign key [message #224747]

Thu, 15 March 2007 05:50

pham
Messages: 17
Registered: August 2006

Junior Member

I have to create this foreign key:

ALTER TABLE tab1
ADD CONSTRAINT fk_tab1_tab2
FOREIGN KEY(col1, col2) REFERENCES tab2(col1, BETWEEN min_val_col AND max_val_col);

and don't know the correct syntax.

Help, help, help

thank for your help

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Re: Foreign key [message #224755 is a reply to message #224747]

Thu, 15 March 2007 06:07

michael_bialik
Messages: 621
Registered: July 2006

Senior Member

Foreign key matches a value of table A to a single value of table B.
You have to use trigger to implement your logic.

HTH.
Michael

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Re: Foreign key [message #224761 is a reply to message #224755]

Thu, 15 March 2007 06:30

pham
Messages: 17
Registered: August 2006

Junior Member

here more info:

the tab1 has 2 columns col1 and col2
the tab2 has a primary key with 3 columns: col1, col2_1 and col2_2

It is a foreign key to build between this two tables, where
tab1.col1 = tab2.col1 and
the value of tab1.col2 is between tab2.col2_1 and tab2.col2_2

how is the syntax for "ALTER TABLE tab1 ..."

thank in advance

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