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Go Back  dBforums > Database Server Software > PostgreSQL > “functional dependency” or “ junction table”?

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Old 01-30-12, 02:19
Asmaa Asmaa is offline
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Join Date: Dec 2011
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“functional dependency” or “ junction table”?

I have a few questions that depend on each other, so I have to ask them together, I really appreciate your help.
Are there differences between normalization and junction table?
Doing normalization by “functional dependency” has the same meaning as creating junction tables?
The example below is an example of junction table or functional dependency?
Can you give me a simple example of what the example below is not?(if it is not junction table give me an example of junction table please and vice versa! )
And how I can create junction table in PostgreSQL?

S_id (PK) |S_name | tutor | school_name | location | tel_no
-----------------------------------------------------------------------------------------------------------------------
24 | John |David | Rose | Newton | 0304-672-3150 , 0352-888-61317
-----------------------------------------------------------------------------------------------------------------------
25 | Mathew| Smith | Gold | Newton| 091654-6452322 , 092356-796310



S_id (PK) |S_name | tutor | school_name
-----------------------------------------------------------
24 | John |David | Rose
-----------------------------------------------------------
25 | Mathew| Smith | Gold



S_id (PK) | location
----------------------------
24 | Newton
----------------------------
25 | Newton



S_id (PK) | tel_no
--------------------------------------
24 | 0304-672-3150
--------------------------------------
24 | 0352-888-61317
--------------------------------------
25 | 091654-6452322
--------------------------------------
25 | 092356-796310
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