SQL Server: Search all tables for a particular GUID

Question

i came across the need to cleanse some data, and i need to find some particular guids (i.e. uniqueidentifiers) in SQL Server°.

i\'ve come up with a stor

Answer 1

You could defer the EXEC until your cursor loop is done. Then, just track the table name inside your loop and if it's the same, add an OR, otherwise end your SELECT and start a new one.

DECLARE @lasttable varchar(255);
SET @lasttable='';
FETCH NEXT FROM abc INTO @tableName, @columnName;
WHILE (@@FETCH_STATUS = 0)
BEGIN
   IF(@lasttable=@tablename) BEGIN
       SET @szQuery = @szQuery + ' OR [' + @columnName + ']=''' + CAST(@searchValue AS varchar(50)) + '''';
   END ELSE BEGIN
       SET @lasttable = @tablename;
       SET @szQuery = @szQuery + 
         'SELECT '''+@tableName+''' AS TheTable, '''+@columnName+''' AS TheColumn '+
         'FROM '+@tableName+' '+
         'WHERE '+@columnName+' = '''+CAST(@searchValue AS varchar(50))+''''
   END
   FETCH NEXT FROM abc INTO @tableName, @columnName;
END
PRINT @szQuery;
EXEC (@szQuery);

You could also create the stored procedure to build a VIEW that does a UNION ALL of all tables and uniqueidentifier fields. Something with a schema like this:

CREATE VIEW all_uuids AS (
    SELECT 'prices' AS tablename, 'BookGUID' as fieldname, ID as primarykey, BookGUID AS guid FROM prices
    UNION ALL SELECT 'prices', 'AuthorGUID', ID, AuthorGUID FROM prices
    UNION ALL SELECT 'othertable', 'otherfield', ID, otherfield FROM othertable
    )

Then, you just need to perform a single SELECT statement on this reusable VIEW to get all of the matching GUIDs. To search within a single table, use a correlated subquery, e.g.:

SELECT * FROM prices WHERE EXISTS (SELECT null FROM all_uuids u WHERE u.primarykey=prices.id AND u.guid=@searchfor AND u.tablename='prices')

That will search across all GUID fields in the prices table. SQL Server is smart enough to not go looking through other tables, and it uses your existing tables' indexes.

By re-using a single view, you only have to go looping through information_schema when you change your schema, not with every query, and the results of a view can be joined more readily than the results of a stored procedure.

---

Answer

Original posters final solution, based on this answer:

CREATE PROCEDURE dbo.FindGUID @searchValue uniqueidentifier AS

/*
    Search all tables in the database for a guid

    Revision History
    6/9/2009: Initally created
    6/10/2009: Build or clause of multiple columns on one table
*/

--DECLARE @searchValue uniqueidentifier
--SET @searchValue = '{2A6814B9-8261-452D-A144-13264433864E}'

DECLARE abc CURSOR FOR
    SELECT 
        c.TABLE_SCHEMA, c.TABLE_NAME, c.COLUMN_NAME
    FROM INFORMATION_SCHEMA.Columns c
        INNER JOIN INFORMATION_SCHEMA.Tables t
        ON c.TABLE_NAME = t.TABLE_NAME
        AND t.TABLE_TYPE = 'BASE TABLE'
    WHERE DATA_TYPE = 'uniqueidentifier'

DECLARE @tableSchema varchar(200)
DECLARE @tableName varchar(200)
DECLARE @columnName varchar(200)
DECLARE @szQuery varchar(8000)
SET @szQuery = ''

DECLARE @lasttable varchar(255);
SET @lasttable='';

OPEN ABC

FETCH NEXT FROM abc INTO @tableSchema, @tableName, @columnName;
WHILE (@@FETCH_STATUS = 0)
BEGIN
   IF(@lasttable=@tablename) 
   BEGIN
      SET @szQuery = @szQuery + ' OR [' + @columnName + ']=''' + CAST(@searchValue AS varchar(50)) + '''';
   END 
   ELSE 
   BEGIN
       SET @lasttable = @tablename;

       IF @szQuery <> '' 
       BEGIN
          PRINT @szQuery
          EXEC ('IF EXISTS (' + @szQuery + ') BEGIN ' + @szQuery + ' END');
       END

       SET @szQuery = 
         'SELECT '''+@tableSchema+'.'+@tableName+''' AS TheTable, '''+@columnName+''' AS TheColumn '+
         'FROM '+@tableName+' '+
         'WHERE '+@columnName+' = '''+CAST(@searchValue AS varchar(50))+''''
   END
   FETCH NEXT FROM abc INTO @tableSchema, @tableName, @columnName;
END

CLOSE abc
DEALLOCATE abc

IF @szQuery <> '' 
BEGIN
    PRINT @szQuery
    EXEC ('IF EXISTS (' + @szQuery + ') BEGIN ' + @szQuery + ' END');
END
GO