While loop to check for existence of randomized value

A bar code is randomly generated, yet it cannot be the same as one that has already been used.   Collisions are pretty common.  So here is how I removed the collisions.

–Generate bar code
UPDATE #Table
SET BarCode = UPPER( dbo.GenerateRandom9CharKey() );

–Check for barcodes that already are used, or for unapproved words
WHILE EXISTS(
SELECT *
FROM #Table
WHERE Barcode IN ( SELECT barcode FROM dbo.Table1 )
)
BEGIN
UPDATE #Table
SET Barcode = UPPER( dbo.GenerateRandom9CharKey() )
WHERE Barcode IN ( SELECT barcode FROM dbo.Table1 )
END

Advertisements
This entry was posted in Uncategorized. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s