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' ___________________________________________________
'
' � Hi-Integrity Systems 2007. All rights reserved.
' www.hisystems.com.au - Toby Wicks
' ___________________________________________________
'
Option Strict On
Option Explicit On
Namespace SQL
Public Class SQLSelectTables
Implements IEnumerable
Private pobjTables As ArrayList = New ArrayList
Private pobjJoins As SQLSelectTableJoins = New SQLSelectTableJoins
Public Sub New()
MyBase.New()
End Sub
Public Function Add() As SQLSelectTable
Return Add("")
End Function
Public Function Add(ByVal strTableName As String) As SQLSelectTable
Dim objTable As SQLSelectTable = New SQLSelectTable
objTable.Name = strTableName
pobjTables.Add(objTable)
Return objTable
End Function
Default Public ReadOnly Property Item(ByVal strTableName As String) As SQLSelectTable
Get
Return DirectCast(pobjTables.Item(TableNameIndex(strTableName)), SQLSelectTable)
End Get
End Property
Default Public ReadOnly Property Item(ByVal intIndex As Integer) As SQLSelectTable
Get
Return DirectCast(pobjTables.Item(intIndex), SQLSelectTable)
End Get
End Property
Public ReadOnly Property Count() As Integer
Get
Return pobjTables.Count()
End Get
End Property
Public Property Joins() As SQLSelectTableJoins
Get
Return pobjJoins
End Get
Set(ByVal Value As SQLSelectTableJoins)
pobjJoins = Value
End Set
End Property
Public Function Exists(ByVal strTableName As String) As Boolean
Return TableNameIndex(strTableName) >= 0
End Function
Public Sub Delete(ByRef objTable As SQLSelectTable)
If pobjTables.Contains(objTable) Then
Throw New ObjectDoesNotExistException
End If
pobjTables.Remove(objTable)
objTable = Nothing
End Sub
Friend ReadOnly Property SQL(ByVal eConnectionType As Database.ConnectionType) As String
Get
Dim strSQL As String
Dim bAddTable As Boolean
For intIndex As Integer = 0 To Me.Count - 1
'Include the table if it's not being used in a join
If pobjJoins Is Nothing Then
bAddTable = True
ElseIf Not pobjJoins.Exists(Me.Item(intIndex)) Then
bAddTable = True
Else
bAddTable = False
End If
If bAddTable Then
strSQL &= Me.Item(intIndex).SQL(eConnectionType)
If intIndex <> Me.Count - 1 Then
strSQL &= ", "
End If
End If
Next
If Not pobjJoins Is Nothing Then
If pobjJoins.SQL(eConnectionType) <> Nothing And strSQL <> Nothing Then
strSQL &= " "
End If
strSQL &= pobjJoins.SQL(eConnectionType)
End If
Return strSQL
End Get
End Property
Private Function TableNameIndex(ByVal strTableName As String) As Integer
Dim objTable As SQLSelectTable
strTableName = strTableName.Trim()
For intIndex As Integer = 0 To Me.Count - 1
objTable = DirectCast(pobjTables.Item(intIndex), SQLSelectTable)
If String.Compare(strTableName, objTable.Name, ignoreCase:=True) = 0 Then
Return intIndex
End If
Next
Return -1
End Function
Private Function GetEnumerator() As System.Collections.IEnumerator Implements System.Collections.IEnumerable.GetEnumerator
Return pobjTables.GetEnumerator
End Function
End Class
End Namespace
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