SQL Server: Tips and Tricks - 2 (2017)
How to search for a String in all Columns in all tables in SQL Server Database
Scenario:
You are working as SQL Server developer / TSQL Developer for finical firm. You are working on analysis data from one of the database. You need to find String let say "Aamir" in all the columns of all the table in SQL server database.
Solution:
This analysis can really help us to find if we are strong a lot of duplicate data and what type of index will work better for us. We often get this type of request from business where they like to check the data in all the tables and further dig into it if found.
We are going to use Cursor to find all the string in all the columns in all the tables in SQL Server Database. As this query is going to run for all the columns of datatype char, nchar, varchar, nvarchar,text and ntext. This can be expensive. If your database is small, you might be good to run.
In cases where your database is big in size, you might want to take the backup and restore on server where users are not connected and run your query there. Or run during those hours when you have less or almost no activity.
USE YourDBName
GO
Declare @SearchString VARCHAR(100)
--Provide the String here. I am using Aamir for search
SET @SearchString='aamir'
DECLARE @DatabaseName VARCHAR(100)
DECLARE @SchemaName VARCHAR(100)
DECLARE @TableName VARCHAR(100)
DECLARE @ColumnName VARCHAR(100)
DECLARE @FullyQualifiedTableName VARCHAR(500)
Declare @DataType VARCHAR(50)
--Create Temp Table to Save Results
IF OBJECT_ID('tempdb..#Results') IS NOT NULL
DROP TABLE #Results
CREATE TABLE #Results (
DatabaseName VARCHAR(100)
,SchemaName VARCHAR(100)
,TableName VARCHAR(100)
,ColumnName VARCHAR(100)
,ColumnDataType VARCHAR(50)
,TotalTableRowCount INT
,StringOccuranceRecordCount INT
)
DECLARE Cur CURSOR
FOR
SELECT C.Table_CataLog
,C.Table_Schema
,C.Table_Name
,C.Column_Name
,'[' + C.Table_CataLog + ']' + '.[' + C.Table_Schema + '].'
+ '[' + C.Table_Name + ']' AS FullQualifiedTableName,
C.Data_Type
FROM information_schema.Columns C
INNER JOIN information_Schema.Tables T ON C.Table_Name = T.Table_Name
AND T.Table_Type = 'BASE TABLE'
and (C.Data_Type like '%CHAR%'
or C.Data_Type like '%Text%')
OPEN Cur
FETCH NEXT
FROM Cur
INTO @DatabaseName
,@SchemaName
,@TableName
,@ColumnName
,@FullyQualifiedTableName
,@DataType
WHILE @@FETCH_STATUS = 0
BEGIN
DECLARE @SQL VARCHAR(MAX) = NULL
SET @SQL = ' Select ''' + @DatabaseName + ''' AS DatabaseName, '''
+ @SchemaName + ''' AS TableName,
''' + @TableName + ''' AS SchemaName,
''' + @ColumnName + ''' AS ColumnName,
''' + @DataType + ''' AS ColumnName,
(Select count(*) from ' + @FullyQualifiedTableName + ' With (Nolock))
AS TotalTableRowCount,
count(*) as StringOccuranceRecordCount from ' + @FullyQualifiedTableName
+ 'With (Nolock) Where '+@ColumnName+' like '''+'%'+ @SearchString+'%'''
-- Print @SQL
INSERT INTO #Results
EXEC (@SQL)
FETCH NEXT
FROM Cur
INTO @DatabaseName
,@SchemaName
,@TableName
,@ColumnName
,@FullyQualifiedTableName
,@DataType
END
CLOSE Cur
DEALLOCATE Cur
SELECT *,
Cast((StringOccuranceRecordCount/Cast(TotalTableRowCount as Numeric(13,1)))*100
AS Numeric(4,1)) AS StringOccurancePercentPerColumn
from #Results
Where StringOccuranceRecordCount<>0
--Drop table #Results
Here are my test results
