Category: SQL Azure

MS SQL Azure – Group child records by parent in order

Lets say we have two tables

A site parent table T001 consisting of two fields
PKID
Sitename

And a planning application child table T002 consisting of three fields
PKID
PKIDT001
PlanRef

We have the following records in the parent table T001
1 – Site01Green
2 – Site02Red
3 – Site03Blue

And the following related children in the planning application table T002;
1 – 1 – 2019/098
1 – 1 – 2018/032
1 – 2 – 2017/987
1 – 3 – 2015/100
1 – 3 – 2014/456
1 – 3 – 2014/657

And we would like to write a query that would create a list combining the two tables showing all the planning applications for each site listed in order.

This is the list we are aiming at
1 – 2018/032,2019/098
2 – 2017/987
3 – 2014/456,2014/657,2015/100

Using SQL Server 2017 or later (including SQL Azure) the following will work

CREATE VIEW [dbo].[View01Sitesandtheirplanapps] AS SELECT PKIDT001, STRING_AGG(PlanRef,',') WITHIN GROUP (ORDER by PlanRef ASC) as PlanRefs
From dbo.T002
GROUP BY PKIDT001;

This can then be combined in a separate view that will include the sitename should it be required – this is a tremendous example the structure of which I will be using often.

SQL SERVER – Create TSQL Trigger to add date to existing record after INSERT or UPDATE

I came across an interesting issue with a web application I have been trying to create. DEFAULTS in SQL Server didn’t seem to be registering when new records were inserted through the web application.

How come? Surely the web application is not bypassing requirements set out by the database.

What I believe is happening is that the web application is explicitly supplying a null value to the dateupdated field and because of this the default value is NOT applied by SQL Server. You are therefore in the strange position of creating a trigger on a column after insert. Normally you would never really do this as that’s specifically what default is for.

Here’s code to create the trigger on the SQL Server that will do just this.

CREATE TRIGGER TR_moddate
On T0001PersonData
AFTER INSERT, UPDATE
AS
BEGIN
UPDATE T0001PersonData SET DATEUPDATED=GETDATE()
WHERE PKID IN (SELECT PKID FROM INSERTED)
END

Some explanation – This updates the field DateUpdated within the table T0001PersonData after an update or an insert. If you have default on a column this may mean that it updates to default then to null then to trigger so you may wish to remove the default on the column. Alternatively you may wish to get the front end to update to the current date. I guess this could have performance issues at scale but my application is pretty small beer so I am happy with this at the moment. I think I prefer to have it at database level as well. It should be noted that INSERTED is actually a ALIAS table created by SQL Server and held in memory that allows for reference to pull out items before they are registered in the database. Leaving out the where clause may have resulted in the application updating the dateupdated column for all records anytime an update or insert was performed. BE WARNED

MS SQL Azure – SQL to Select Distinct list of Child Records based on a Maximum or Minimum Child Field Value

Following on from the previous post I wanted to know the syntax for SQL to do the same but in SQL Azure. 

SELECT * FROM dbo.T02AttendanceGame T1    
WHERE Attendance = (
   SELECT max(Attendance)
   FROM dbo.T02AttendanceGame T2
   WHERE T1.FKID=T2.FKID
);

I created the same tables that I created for the MS Access example with the same field names but within a SQL Azure database.

Here’s the same SQL but then creating a view called rather unimaginatively ‘View01’

CREATE VIEW VIEW01 AS SELECT * FROM dbo.T02AttendanceGame T1    
WHERE Attendance = (
   SELECT max(Attendance)
   FROM dbo.T02AttendanceGame T2
   WHERE T1.FKID=T2.FKID
);

MS SQL Azure – Take Complete Backup of Azure Database (Structure and Data)

SQL Azure as part of the service offers a number of differing back up options as standard – however you may wish to take additional backups which for instance you can load onto a local version of SQL Server (Express or Enterprise). Here’s a quick rundown of one method of doing this.

Firstly open up your version of SQL Server Management Studio and navigate to the instance and database that you wish to backup

Highlight the database in this case DB001 and right click -Select Tasks and Export Data-Tier Application

Choose an appropriate location to put the backup file

Review the summary of items that will be backed up and then hit Finish

There will be a run down of how the export has worked

And just a check to see the exported file in the directory

Upload Shape Files into SQL Azure using OGR2OGR – Explanation of MS SQL Azure Connection String to be placed within OGR2OGR Command Line

Lets say you have a SQL Azure Server with the following parameters

SQL Azure Instance : azureinstance1
Database name within Instance : TouristDB1
Your User Name is : tom
Password is : Edinburgh

The SQLAzure connection string would be
MSSQL:Server=tcp:azureinstance1.database.windows.net;Database=TouristDB1;
Uid=tom@azureinstance1.database.windows.net;Pwd=Edinburgh;

and the full OGR2OGR to import Command Line Instruction for a shape file called Monuments.shp would be..

ogr2ogr -overwrite -f MSSQLSpatial "MSSQL:Server=tcp:azureinstance1.database.windows.net;Database=TouristDB1;
Uid=tom@azureinstance1.database.windows.net;Pwd=Edinburgh;" "C:\Monuments.shp"

VBA Function to Create Table of Import strings using OGR2OGR targeting a SQL Server

Do you have many shape files you wish to import into a local SQL Server Database so that you can display them in QGIS or serve them on Geoserver?
Here’s a short function I wrote that will take a table called T0001OpenStreetMapLayers with fields PKID/Name/Directory/Type/Flag – and produce OGR strings that can then be used to load them into a local SQL Server / SQL Express or SQL Azure

For this to be useful you will need
A version of QGIS
A local SQL Server copy (in this case SQL Server Express)
A database within your copy called OpenStreetMap
All shape files in the same directory
You will also need to figure out how to get all those shape files into the table T0001OpenStreetMapLayers table
A starting database with 2 tables
T0001OpenStreetMapLayers with populated fields PKID/Name/Directory/Type/Flag
T0002OGRStrings blank table with fields PKID/CommandLine – This is where all the Command Line Strings will be stored

Public Function CreateTableOGR2OGRString()

Dim rs1 As DAO.Recordset
Dim rs2 As DAO.Recordset
Dim db As DAO.Database
Dim O2O As String
Dim LCounter As Integer
Dim strQuote As String
Set db = CurrentDb
strQuote = Chr$(34)


LCounter = 1
While LCounter < 3000
LCounter = LCounter < 3000

Set rs1 = CurrentDb.OpenRecordset("SELECT T0001OpenStreetMapLayers.PKID, T0001OpenStreetMapLayers.Name, T0001OpenStreetMapLayers.Directory, T0001OpenStreetMapLayers.Type, T0001OpenStreetMapLayers.Flag FROM T0001OpenStreetMapLayers WHERE (((T0001OpenStreetMapLayers.Type)=1) AND ((T0001OpenStreetMapLayers.Flag)=0 Or (T0001OpenStreetMapLayers.Flag) Is Null));")
O2O = "ogr2ogr -append -f MSSQLSpatial " & strQuote & "MSSQL:server=DESKTOP-JECT7QO\SQLEXPRESS;database=OpenStreetMap;trusted_connection=yes" & strQuote & " " & strQuote & rs1!Directory & rs1!Name & ".shp" & strQuote & ""


rs1.Edit
rs1!Flag = 1
rs1.Update
rs1.MoveNext
rs1.Close

Set rs2 = CurrentDb.OpenRecordset("T0002OGRStrings")
With rs2
.AddNew
rs2!CommandLine = O2O
rs2.Update
rs2.Close
End With
Wend
End Function

For SQL Azure target databases replace the yellow connection string with something resembling;

MSSQL:Server=tcp:azureinstance1.database.windows.net;Database=TouristDB1;
Uid=tom@azureinstance1.database.windows.net;Pwd=Edinburgh;

There are multiple methods of finding the name of your SQL Instance – Ignoring the fact that you won’t be able to connect to it if you don’t know it – Within SSMS you can right click on the instance and look to properties but the name itself is usually in the instance path of SSMS as well.

MS SQL Azure to MS Access – Using VBA to Dump Azure Tables into MS Access Tables

The first thing you need to get sorted when moving to SQL Azure is having the ability to get your information out and safe if needs be. When experimenting with MS Azure and for applications that don’t have sensitive information it is nice to have that information available in an easily accessible format. Here are a series of functions that will copy Azure Tables linked to database into local MS Access tables with the prefix ZCOPY.

The starting point in this should be an MS Access database that should be linked to your SQL Azure Database. Only those tables that are linked will be copied. Remember the 2GB limit on Access.

I think I have got all the functions here that are required to make it work and include the complete module at the bottom but first I will breakdown the modules and list describe what each of the functions do.

First create a table to store the list of tables in the Azure Database

Public Function CreateTableT0001AzureTablesGlobal()
 
     Dim dbs As Database
     Set dbs = CurrentDb
 
        dbs.Execute "CREATE TABLE T0001AzureTablesGlobal " _
        & "(PKID AUTOINCREMENT, " _
        & "AzureTableName CHAR CONSTRAINT PKID " _
        & "PRIMARY KEY);"
   
End Function

Now Create a Function that will hold the SQL that takes the tables and makes them locally.

Public Function CreateTableT0002SQL()
 
     Dim dbs As Database
     Set dbs = CurrentDb
 
        dbs.Execute "CREATE TABLE T0002SQL " _
        & "(PKID AUTOINCREMENT, " _
        & "SQL MEMO CONSTRAINT PKID " _
        & "PRIMARY KEY);"
 
   
End Function

A function that allows for stepping through the table

Public Function AddByteColumn(TblName As String, FieldName As String)
'Just use byte data type as only going to use this for a flag

DoCmd.RunSQL "AlTER TABLE [" & TblName & "] ADD COLUMN " & FieldName & " BYTE;"

End Function

Step through the Linked Azure Tables and poupulate table T001 with their names

Public Function CreateandPopulateListofDBOTableNames()

'These will typically be the names of the SQL Server tables this should work both with SQL Server and SQL Azure

Dim db As DAO.Database
Dim tdf As DAO.TableDef
Dim rstList As DAO.Recordset

'Call CreateTableT0001AzureTablesGlobal

Set rstList = CurrentDb.OpenRecordset("T0001AzureTablesGlobal")
Set db = CurrentDb

For Each tdf In db.TableDefs
    ' ignore system and temporary tables and tables starting with T - personal choice option
    If Not (tdf.Name Like "MSys*" Or tdf.Name Like "~*" Or tdf.Name Like "T*") Then
       With rstList
       .AddNew
       rstList!AzureTableName = tdf.Name
       rstList.Update
      End With
    End If
    
Next

Set tdf = Nothing
Set db = Nothing

End Function

The next function is required to strip out additional spaces in names

Public Function FindXReplaceY(FixTable As String, FixColumn As String, X As String, Y As String) As Variant

Dim strSQL As String

strSQL = "UPDATE [" & FixTable & "] SET [" & FixTable & "].[" & FixColumn & "] = REPLACE([" & FixColumn & "]," & Chr$(34) & X & Chr$(34) & "," & Chr$(34) & Y & """);"

DoCmd.RunSQL strSQL

End Function

We can now write the VBA that will write the make table SQL that once run will put one make table query into the maketableSQL table for each Azure table.

Public Function CreateMakeTableSQL()

On Error GoTo Err_CreateMakeTableSQL
Dim rstSQL As DAO.Recordset
Dim rstSQLx As DAO.Recordset
Dim dbc As DAO.Database
Dim SQLStringAdd As String
Dim LCounter As Long

Set dbc = CurrentDb

LCounter = 1
While LCounter < 9000
LCounter = LCounter + 1
Set rstSQL = CurrentDb.OpenRecordset("SELECT T0001AzureTablesGlobal.PKID, T0001AzureTablesGlobal.AzureTableName, T0001AzureTablesGlobal.XFLag1 FROM T0001AzureTablesGlobal WHERE (((T0001AzureTablesGlobal.XFLag1) Is Null));")

SQLStringAdd = "SELECT * INTO COPY" & rstSQL!AzureTableName & " FROM " & rstSQL!AzureTableName & ";"

Set rstSQLx = CurrentDb.OpenRecordset("T0002SQL")
With rstSQLx
.AddNew
rstSQLx!SQL = SQLStringAdd
rstSQLx.Update
rstSQLx.Close
End With

With rstSQL
rstSQL.Edit
rstSQL!XFLag1 = 1
rstSQL.Update
rstSQL.MoveNext
rstSQL.Close
End With

Wend

Exit_CreateMakeTableSQL:
    Exit Function

Err_CreateMakeTableSQL:
Select Case Err.Number
 Case 3021
   Resume Exit_CreateMakeTableSQL
  Case Else
  Resume Exit_CreateMakeTableSQL
  End Select
 
End Function

And finally Run all the queries

Public Function RunQueriesFromTable2(SQLSource As String)

DoCmd.SetWarnings False

Dim StartTime As Date
Dim EndTime As Date
Dim rstZ As DAO.Recordset
Dim strSQL2 As String

StartTime = Now()

Set rstZ = CurrentDb.OpenRecordset(SQLSource)

Do Until rstZ.EOF

strSQL2 = rstZ!SQL
DoCmd.RunSQL strSQL2
rstZ.MoveNext

Loop

DoCmd.SetWarnings True

EndTime = Now()

MsgBox "Finished ALL SQL queries! Process started at " & StartTime & " and finished at " & EndTime

End Function

And a script to pull all of this together

Public Function GetAzureScript()

DoCmd.SetWarnings False
Call CreateTableT0001AzureTablesGlobal
Call CreateandPopulateListofDBOTableNames
Call FindXReplaceY("T0001AzureTablesGlobal", "AzureTablename", " ", "")
Call FindXReplaceY("T0001AzureTablesGlobal", "AzureTablename", Chr(10), "")
Call AddByteColumn("T0001AzureTablesGlobal", "XFLag1")
Call CreateTableT0002SQL
Call CreateMakeTableSQL
Call FindXReplaceY("T0002SQL", "SQL", " ", "")
Call FindXReplaceY("T0002SQL", "SQL", Chr(10), "")
Call FindXReplaceY("T0002SQL", "SQL", "SELECT*INTOCOPY", "SELECT * INTO ZCOPY")
Call FindXReplaceY("T0002SQL", "SQL", "FROM", " FROM ")
Call RunQueriesFromTable("T0002SQL")
DoCmd.SetWarnings True

End Function

The complete module

Option Compare Database
Option Explicit

Public Function GetAzureScript()

DoCmd.SetWarnings False
Call CreateTableT0001AzureTablesGlobal
Call CreateandPopulateListofDBOTableNames
Call FindXReplaceY("T0001AzureTablesGlobal", "AzureTablename", " ", "")
Call FindXReplaceY("T0001AzureTablesGlobal", "AzureTablename", Chr(10), "")
Call AddByteColumn("T0001AzureTablesGlobal", "XFLag1")
Call CreateTableT0002SQL
Call CreateMakeTableSQL
Call FindXReplaceY("T0002SQL", "SQL", " ", "")
Call FindXReplaceY("T0002SQL", "SQL", Chr(10), "")
Call FindXReplaceY("T0002SQL", "SQL", "SELECT*INTOCOPY", "SELECT * INTO ZCOPY")
Call FindXReplaceY("T0002SQL", "SQL", "FROM", " FROM ")
Call RunQueriesFromTable2("T0002SQL")
DoCmd.SetWarnings True

End Function

Public Function CreateandPopulateListofDBOTableNames()

'These will typically be the names of the SQL Server tables this should work both with SQL Server and SQL Azure

Dim db As DAO.Database
Dim tdf As DAO.TableDef
Dim rstList As DAO.Recordset

'Call CreateTableT0001AzureTablesGlobal

Set rstList = CurrentDb.OpenRecordset("T0001AzureTablesGlobal")
Set db = CurrentDb

For Each tdf In db.TableDefs
    ' ignore system and temporary tables and tables starting with T - personal choice option
    If Not (tdf.Name Like "MSys*" Or tdf.Name Like "~*" Or tdf.Name Like "T*") Then
       With rstList
       .AddNew
       rstList!AzureTableName = tdf.Name
       rstList.Update
      End With
    End If
    
Next

Set tdf = Nothing
Set db = Nothing

End Function

Public Function FindXReplaceY(FixTable As String, FixColumn As String, X As String, Y As String) As Variant

Dim strSQL As String

strSQL = "UPDATE [" & FixTable & "] SET [" & FixTable & "].[" & FixColumn & "] = REPLACE([" & FixColumn & "]," & Chr$(34) & X & Chr$(34) & "," & Chr$(34) & Y & """);"

DoCmd.RunSQL strSQL

End Function

Public Function CreateTableT0001AzureTablesGlobal()
 
     Dim dbs As Database
     Set dbs = CurrentDb
 
        dbs.Execute "CREATE TABLE T0001AzureTablesGlobal " _
        & "(PKID AUTOINCREMENT, " _
        & "AzureTableName CHAR CONSTRAINT PKID " _
        & "PRIMARY KEY);"
 
   
End Function

Public Function CreateTableT0002SQL()
 
     Dim dbs As Database
     Set dbs = CurrentDb
 
        dbs.Execute "CREATE TABLE T0002SQL " _
        & "(PKID AUTOINCREMENT, " _
        & "SQL MEMO CONSTRAINT PKID " _
        & "PRIMARY KEY);"
 
   
End Function

Public Function AddByteColumn(TblName As String, FieldName As String)
'Just use byte data type as only going to use this for a flag

DoCmd.RunSQL "AlTER TABLE [" & TblName & "] ADD COLUMN " & FieldName & " BYTE;"

End Function

Public Function CreateMakeTableSQL()

On Error GoTo Err_CreateMakeTableSQL
Dim rstSQL As DAO.Recordset
Dim rstSQLx As DAO.Recordset
Dim dbc As DAO.Database
Dim SQLStringAdd As String
Dim LCounter As Long

Set dbc = CurrentDb

LCounter = 1
While LCounter < 9000
LCounter = LCounter + 1
Set rstSQL = CurrentDb.OpenRecordset("SELECT T0001AzureTablesGlobal.PKID, T0001AzureTablesGlobal.AzureTableName, T0001AzureTablesGlobal.XFLag1 FROM T0001AzureTablesGlobal WHERE (((T0001AzureTablesGlobal.XFLag1) Is Null));")
SQLStringAdd = "SELECT * INTO COPY" & rstSQL!AzureTableName & " FROM " & rstSQL!AzureTableName & ";"

Set rstSQLx = CurrentDb.OpenRecordset("T0002SQL")
With rstSQLx
.AddNew
rstSQLx!SQL = SQLStringAdd
rstSQLx.Update
rstSQLx.Close
End With

With rstSQL
rstSQL.Edit
rstSQL!XFLag1 = 1
rstSQL.Update
rstSQL.MoveNext
rstSQL.Close
End With

Wend

Exit_CreateMakeTableSQL:
    Exit Function

Err_CreateMakeTableSQL:
Select Case Err.Number
 Case 3021
   Resume Exit_CreateMakeTableSQL
  Case Else
  Resume Exit_CreateMakeTableSQL
  End Select
 
End Function

Public Function RunQueriesFromTable2(SQLSource As String)

DoCmd.SetWarnings False

Dim StartTime As Date
Dim EndTime As Date
Dim rstZ As DAO.Recordset
Dim strSQL2 As String

StartTime = Now()

Set rstZ = CurrentDb.OpenRecordset(SQLSource)

Do Until rstZ.EOF

strSQL2 = rstZ!SQL
DoCmd.RunSQL strSQL2
rstZ.MoveNext

Loop

DoCmd.SetWarnings True

EndTime = Now()

MsgBox "Finished ALL SQL queries! Process started at " & StartTime & " and finished at " & EndTime

End Function

MS Access front end – MS SQL Azure back end Link to Configuration Set UP FMS Group

This is an excellent article on linking MS Access to SQL Azure – which is just great if you are wanting to use your VBA skills direct on your SQL Database.

FMS Professional Solutions Group – Luke Chung MVP article

It should be noted that the Primary Key will need to be set to Integer in the SQL Database rather than Big Int otherwise it will appear as #DELETED# when you go in and view the data. This may not be an issue going forward for some users of Office 365 Access 2016 as Microsoft are introducing support for Big Int in MS Access. Congratulations to Microsoft on that small but important change.

Upload XLS information to a specific table or new table within an SQL Azure Database

I have started experimenting with Microsoft Azure if you haven’t already you can get a free experimentation account here;

Microsoft Azure Trial account with £125 credit

This gets your registered on Microsoft’s cloud and after a free trial period you will be able to continue with a Pay as You go Account which depending on the services that you go for can start at very cheap rates.

In order for this to work you will need the following
1) Microsoft Azure account
2) An SQL Azure Database
3) SQL Server Management Studio downloaded and installed on the machine you will be uploading from, this can be obtained from SSMS download link be warned its over 800mb. Here I use SSMS 2016
4) Know your server name this is generally [Yourname].database.windows.net
5) Login and Password (I use SQL Server Authentication)

Testing things out I have been using the Web Apps Service to run a website and connect to an SQL Azure Database – both on the cheapest options.

What makes the website particularly cheap is that it can be stopped and started and by paying for it by the minute you can really get a powerful demonstration sites up and running and stop them immediately after the demonstration for very little money.

So after having created an Azure SQL database (Microsoft Create Azure Database Tutorial)I wanted to get a decent number of records into it. Which would be the starting position when taking on most work.
Here I use the Lichfield Planning Application information previously referred to in this post QGIS Import. What I did was take the 45,000 records of planning applications from the shape file. I did this by opening up the dbf file of the shape collection in Excel 2003 and then saving it in excel format. This will be used later to import into the database.

Having your excel file ready the next step is to open up SQL Server Management Studio and connect to your Azure Database. The parameters with regard to username and servername will have been setup when you created your Azure database it is important that when you create your Azure database you somehow record these details.

Next highlight the database – in my case this was DB001 and right click to get tasks.

At this point you enter the import wizard windows dialog boxes and having passed the opening welcome screen , a screen that can be turned off for subsequent navigations, you should hit your first screen that allows you to define the format of the file that should be imported.

The next step is about the only one that is slightly confusing – you are given a number of different options for the target – for me SQL Server Native Client 11.0 worked for me.

Now using the previous parameters specific to your database server and your database name complete the next dialog.

The next dialog asks you whether you want to copy all information or want to write a query to filter the information to be imported. For my example I chose the all import item. Here I select the database and then I am able to see the from and too destinations.

If you wish to import into an existing table use the drop down to select tables from the database – if you wish to import into a new table you can type in the name of the new table within the square brackets.

Here I create a new table called T010Test and import and then continue through the import wizard dialogs until on completion of import you should see a similar screen to that below. It is possible to go into the edit mappings if you are copying into a table that already exists. This will give you a preview showing to what extent the mapping will be successful and how the fields map. You may wish to alter the names of columns to match your target table at this point.

Microsoft Azure – moving to the cloud

I must confess I do love MS Access and I have a number of projects that I suspect will always remain as are – these are ones that are highly complex but very personal that I really don’t need to share. Even some projects that because of their sensitivity I would never want to share but despite the difficulty of designing really user friendly user interfaces on the web the ability to distribute your applications to everyone in the world is a very powerful attractor which is quite clearly going to be a game changer.

I have therefore started to experiment with data driven online applications and so far I am impressed.

To get started you will first want to sign up with an Azure account.
Azure Portal Sign In

I can see in the future I will probably be using Access as a desktop platform for writing queries and personal content curation with SQL Azure for projects where I need to communicate with others linked through the apps service in the Azure portal.