Select Primary Key

[akcreative]

Hi

Is there any way to select Primary key from table . If you do not know your
primary key. I mean can we make any condition or check in which select
statement will only select the primary key.

Thanks
Jon

[Dan Bracuk]

In some databases you can find out the primary key by querying the system tables, assuming you have permission to do so. The specifics are db dependent.

[akcreative]

Hi

I can see many System tables in my database. Can you please give me an example. That will help me alot. Thanks, Jon

[paross1]

On a philosophical note, it seems to me that if you don't know enough about
your data model / database / schema to know what your keys are, then you
probably shouldn't be doing any queries until you do. Kind of like hunting in a
cave without a flashlight.

Phil

[akcreative]

Thanks alot for your help.

I am using SQL server. Actually I am trying to create a CFC that will check
the database dependency. I know my databse well. But I am trying to create a
tree relationship of database programically

Thanks Jon

[paross1]

You may want to take a look at SQL Server Books online (BOL) and research
Catalog Functions.

For example:

SQLPrimaryKeys uses the catalog stored procedure sp_pkeys to report primary
key participants from a table. Though a table may have a column or columns that
can serve as unique row identifiers, tables created without a PRIMARY KEY
constraint return an empty result set to SQLPrimaryKeys. The ODBC function
SQLSpecialColumns reports row identifier candidates for tables without primary
keys.

Phil

[akcreative]

hi

did not have any clue how can i use SQLPrimaryKeys

thanks

[paross1]

I take it that you don't have access to BooksOnLine? It is free to download
from Microsoft, and you would be well advised to do so.

You could look at your sysconstraints table, but then you get into table IDs
and column IDs and status flags, etc. Not much help without a roadmap.

Phil

[Sojovi]

Paross1 is right. Books Online and a little of sweat. Anyway, a little help
this time :

SELECT kcu.table_name,kcu.column_name
FROMinformation_schema.TABLE_CONSTRAINTS
tc,information_schema.KEY_COLUMN_USAGE kcu
WHERE tc.constraint_type='PRIMARY KEY' AND
tc.CONSTRAINT_NAME=kcu.CONSTRAINT_NAME

Regards