Tagdatabase

Replace string in a field

The example replaces the stringĀ height=”480″ with the stringĀ height=”320″.

UPDATE Blog SET myPost = REPLACE(CAST(myPost AS varchar(MAX)),’height=”480″‘, ‘height=”320″‘)
FROM Blog
WHERE CHARINDEX(‘height=”480″‘,CAST(myPost as varchar(MAX)))>0
AND myKey=2469

VB.NET Module for SQL Database

Imports System.Data.SqlClient

Module modDatabase

Public conn As New SqlClient.SqlConnection
Public myReader As SqlDataReader

Public dsRecords As New DataSet
Public daRecords As New SqlDataAdapter
Public MaxRecords As Integer

Public Sub OpenDatabase()
CloseSQLReader()
CloseDatabase()

conn.ConnectionString = “Server=.\sqlexpress;Database=DATABASE;Trusted_Connection=True;”
conn.Open()
End Sub

 

Public Sub CloseDatabase()
Try
conn.Close()
conn.Dispose()
Catch ex As Exception
Application.DoEvents()
End Try
End Sub

 

Public Sub launchBrowser(ByVal browser As String, ByVal url As String)
Try
Process.Start(browser, url)
Catch ex As Exception
Application.DoEvents()
‘MessageBox.Show(ex.Message)
End Try
End Sub

 

Public Sub CloseSQLReader()
Try
myReader.Close()
Catch ex As Exception
Application.DoEvents()
End Try
End Sub

 

Public Sub ReadSqlData(ByVal sqlSelect As String)
Dim myCommand As New SqlCommand(sqlSelect, conn)
myReader = myCommand.ExecuteReader()
End Sub

 

Public Function ExecuteSqlCommand(ByVal sqlSelect As String) As Boolean
Dim flg As Boolean = False
Dim myCommand As New SqlCommand(sqlSelect, conn)

Try
flg = myCommand.ExecuteNonQuery
Catch
flg = False
End Try

Return flg
End Function

 

Public Sub HoldYourPants(ByVal Seconds As Integer)
System.Threading.Thread.Sleep(Seconds * 1000)
Application.DoEvents()
End Sub

End Module

SQL Left Function

The LEFT function allows you to extract a substring from a string, starting from the left-most character.

LEFT( string, number_of_characters )

Example:

SELECT LEFT('TechOnTheNet.com', 4);
Result: 'Tech'

SQL Delete Duplicate Records

This example shows how to remove duplicate uid records from a table named AD_Users

WITH CTE AS
(
SELECT ROW_NUMBER() OVER (PARTITION BY uid ORDER BY uid) AS Row, * FROM AD_Users
)
DELETE FROM CTE
WHERE ROW <> 1

SQL List of Database Sizes

The following SQL command lists each database on a given server shows its data file size.

with fs
as
 (
  select database_id, type, size * 8.0 / 1024 size
  from sys.master_files
 )
select 
 name,
 (select sum(size) from fs where type = 0 and fs.database_id = db.database_id) DataFileSizeMB,
 (select sum(size) from fs where type = 1 and fs.database_id = db.database_id) LogFileSizeMB
from sys.databases db