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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 SQLCreateIndex
Inherits SQLStatement
Private pstrName As String
Private pstrTableName As String
Private pbIsUnique As Boolean
Private pobjFields As SQLIndexFields = New SQLIndexFields
Public Sub New()
End Sub
Public Sub New(ByVal strIndexName As String, ByVal strTableName As String, ByVal strFieldNames() As String)
Me.Name = strIndexName
Me.TableName = strTableName
For Each strFieldName As String In strFieldNames
Me.Fields.Add(strFieldName)
Next
End Sub
Public Sub New(ByVal strIndexName As String, ByVal strTableName As String, ByVal strFieldNames() As String, ByVal bIsUnique As Boolean)
Me.New(strIndexName, strTableName, strFieldNames)
pbIsUnique = bIsUnique
End Sub
Public Property Name() As String
Get
Return pstrName
End Get
Set(ByVal Value As String)
pstrName = Value.Trim
End Set
End Property
Public Property TableName() As String
Get
Return pstrTableName
End Get
Set(ByVal Value As String)
pstrTableName = Value.Trim
End Set
End Property
Public Property IsUnique() As Boolean
Get
Return pbIsUnique
End Get
Set(ByVal Value As Boolean)
pbIsUnique = Value
End Set
End Property
Public ReadOnly Property Fields() As SQLIndexFields
Get
Return pobjFields
End Get
End Property
Public Overrides ReadOnly Property SQL() As String
Get
Dim strSQL As String
'Although the index name is optional with SQL Server it is not optional with MySQL
If Me.Name = Nothing Then
Throw New DatabaseObjectsException("IndexName has not been set.")
End If
If Me.TableName = Nothing Then
Throw New DatabaseObjectsException("TableName has not been set.")
End If
strSQL = _
"CREATE " & UniqueString() & "INDEX " & _
SQLConvertIdentifierName(Me.Name, Me.ConnectionType) & " ON " & _
SQLConvertIdentifierName(Me.TableName, Me.ConnectionType) & _
" (" & pobjFields.SQL(Me.ConnectionType) & ")"
Return strSQL
End Get
End Property
Private Function UniqueString() As String
If pbIsUnique Then
Return "UNIQUE "
Else
Return ""
End If
End Function
End Class
Public Class SQLIndexFields
Private pcolFields As ArrayList = New ArrayList
Friend Sub New()
End Sub
Public Function Add() As SQLIndexField
Return Add("", OrderBy.Ascending)
End Function
Public Function Add( _
ByVal strFieldName As String) As SQLIndexField
Return Add(strFieldName, OrderBy.Ascending)
End Function
Public Function Add( _
ByVal strFieldName As String, _
ByVal eOrder As OrderBy) As SQLIndexField
Dim objField As SQLIndexField = New SQLIndexField
With objField
.Name = strFieldName
.Order = eOrder
End With
pcolFields.Add(objField)
Add = objField
End Function
Friend ReadOnly Property SQL(ByVal eConnectionType As Database.ConnectionType) As String
Get
Const cstrSeperator As String = ", "
Dim strSQL As String
For Each objField As SQLIndexField In pcolFields
strSQL &= objField.SQL(eConnectionType) & cstrSeperator
Next
Return strSQL.Substring(0, strSQL.Length - cstrSeperator.Length) 'remove the last comma and space
End Get
End Property
End Class
Public Class SQLIndexField
Private pstrName As String
Private peOrder As OrderBy
Friend Sub New()
End Sub
Public Property Name() As String
Get
Return pstrName
End Get
Set(ByVal Value As String)
pstrName = Value.Trim
End Set
End Property
Public Property Order() As OrderBy
Get
Return peOrder
End Get
Set(ByVal Value As OrderBy)
peOrder = Value
End Set
End Property
Friend ReadOnly Property SQL(ByVal eConnectionType As Database.ConnectionType) As String
Get
Return SQLConvertIdentifierName(Me.Name, eConnectionType) & OrderString()
End Get
End Property
Private Function OrderString() As String
If peOrder = OrderBy.Descending Then
Return " DESC"
Else
Return ""
End If
End Function
End Class
End Namespace
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