Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium

x
?
Solved

VB.net Get a count of the number of primary keys in a SQL table

Posted on 2014-11-10
3
Medium Priority
?
252 Views
Last Modified: 2014-11-10
Hi

I use the following code to get the primary key for a SQL table. If the table has more than one primary key
how do I get a count of the number of primary keys? Thanks

            sSQL = "SELECT column_name "
                sSQL = sSQL & "FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE "
                sSQL = sSQL & "WHERE OBJECTPROPERTY(OBJECT_ID(constraint_name), 'IsPrimaryKey') = 1"
                sSQL = sSQL & "AND table_name = '" & oTableName & "'"

                Dim connection As New SqlConnection(Globals.ThisAddIn.oRIGHT.lblConnectionString.Text)
                Dim cmd As New SqlCommand(sSQL, connection)
                connection.Open()
                Get_Primary_Key = cmd.ExecuteScalar().ToString
                connection.Close()
0
Comment
Question by:Murray Brown
3 Comments
 
LVL 24

Assisted Solution

by:Phillip Burton
Phillip Burton earned 1000 total points
ID: 40432381
A table can only have one primary key.

More than one column can be engaged in the primary key, but there will only be one primary key in the table.
0
 
LVL 36

Accepted Solution

by:
ste5an earned 1000 total points
ID: 40432487
E.g.

 
USE AdventureWorks2012;

SELECT  KC.name ,
        C.name 
FROM    sys.schemas S
        INNER JOIN sys.tables T ON T.schema_id = S.schema_id
        INNER JOIN sys.key_constraints KC ON KC.parent_object_id = T.object_id
        INNER JOIN sys.index_columns IC ON IC.object_id = T.object_id
                                           AND IC.index_id = KC.unique_index_id
        INNER JOIN sys.columns C ON C.object_id = T.object_id
                                    AND C.column_id = IC.column_id
WHERE   S.name = 'Production'
        AND T.name = 'ProductInventory'
	AND KC.type = 'PK';

Open in new window

0
 

Author Closing Comment

by:Murray Brown
ID: 40432524
Thanks for clarifying that a table can only one primary key. Also thanks for the code
0

Featured Post

NFR key for Veeam Agent for Linux

Veeam is happy to provide a free NFR license for one year.  It allows for the non‑production use and valid for five workstations and two servers. Veeam Agent for Linux is a simple backup tool for your Linux installations, both on‑premises and in the public cloud.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

An alternative to the "For XML" way of pivoting and concatenating result sets into strings, and an easy introduction to "common table expressions" (CTEs). Being someone who is always looking for alternatives to "work your data", I came across this …
One of the most important things in an application is the query performance. This article intends to give you good tips to improve the performance of your queries.
This video shows, step by step, how to configure Oracle Heterogeneous Services via the Generic Gateway Agent in order to make a connection from an Oracle session and access a remote SQL Server database table.
Using examples as well as descriptions, and references to Books Online, show the documentation available for datatypes, explain the available data types and show how data can be passed into and out of variables.
Suggested Courses

579 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question