sql - How to find a string inside a entire database?

Question

I have one specific string, such as "123abcd" for example but I don't know the name of the table or even the name of the column inside the table on my SQL Server Database. I want to find it with a select and show all columns of the related string, so I was wondering something like:

select * from Database.dbo.* where * like  '%123abcd%'

For obvious reasons it doens't work, but there is a simple way to create a select statement to do something like this?

Answer 1

This will work:

DECLARE @MyValue NVarChar(4000) = 'something';

SELECT S.name SchemaName, T.name TableName
INTO #T
FROM sys.schemas S INNER JOIN
     sys.tables T ON S.schema_id = T.schema_id;

WHILE (EXISTS (SELECT * FROM #T)) BEGIN
  DECLARE @SQL NVarChar(4000) = 'SELECT * FROM $$TableName WHERE (0 = 1) ';
  DECLARE @TableName NVarChar(1000) = (
    SELECT TOP 1 SchemaName + '.' + TableName FROM #T
  );
  SELECT @SQL = REPLACE(@SQL, '$$TableName', @TableName);

  DECLARE @Cols NVarChar(4000) = '';

  SELECT
    @Cols = COALESCE(@Cols + 'OR CONVERT(NVarChar(4000), ', '') + C.name + ') = CONVERT(NVarChar(4000), ''$$MyValue'') '
  FROM sys.columns C
  WHERE C.object_id = OBJECT_ID(@TableName);

  SELECT @Cols = REPLACE(@Cols, '$$MyValue', @MyValue);
  SELECT @SQL = @SQL + @Cols;

  EXECUTE(@SQL);

  DELETE FROM #T
  WHERE SchemaName + '.' + TableName = @TableName;
END;

DROP TABLE #T;

A couple caveats, though. First, this is outrageously slow and non-optimized. All values are being converted to nvarchar simply so that they can be compared without error. You may run into problems with values like datetime not converting as expected and therefore not being matched when they should be (false negatives).

The WHERE (0 = 1) is there to make building the OR clause easier. If there are not matches you won't get any rows back.