I'm trying to use the following code to examine table schema for SQL 2000. But when I do, the IsKey value is null or blank. I tried this on two different tables - a State table with a char(2) primary key containing the state abbreviation and a Trend table which has an identity column as the primary key.
Public Shared Function GetSchema(ByVal sTableAs String)As String Dim sbAs New StringBuilderDim oConnAs SqlConnection = OpenConn()Dim cmdAs SqlCommand =New SqlCommand("SELECT * FROM " & sTable, oConn)Dim drAs SqlDataReader = cmd.ExecuteReader(CommandBehavior.SchemaOnly)Dim dtAs DataTable = dr.GetSchemaTable() dr.Close() oConn.Close()For icAs Integer = 0To dt.Columns.Count - 1 sb.Append(ic &":" & CNull(dt.Columns(ic).ColumnName) &" ")Next sb.Append(vbCrLf)For irAs Integer = 0To dt.Rows.Count - 1For icAs Integer = 0To dt.Columns.Count - 1 sb.Append(ic &":" & CNull(dt.Rows(ir).Item(ic).ToString) &" ")Next sb.Append(vbCrLf)Next Return sb.ToStringEnd Function Here's the output from the function:
? datahelper.GetSchema("State")
"0:ColumnName 1:ColumnOrdinal 2:ColumnSize 3:NumericPrecision 4:NumericScale 5:IsUnique 6:IsKey 7:BaseServerName 8:BaseCatalogName 9:BaseColumnName 10:BaseSchemaName 11:BaseTableName 12:DataType 13:AllowDBNull 14:ProviderType 15:IsAliased 16:IsExpression 17:IsIdentity 18:IsAutoIncrement 19:IsRowVersion 20:IsHidden 21:IsLong 22:IsReadOnly 23:ProviderSpecificDataType 24:DataTypeName 25:XmlSchemaCollectionDatabase 26:XmlSchemaCollectionOwningSchema 27:XmlSchemaCollectionName 28:UdtAssemblyQualifiedName 29:NonVersionedProviderType
0:StateCode 1:0 2:2 3:255 4:255 5:False 6: 7: 8: 9:StateCode 10: 11: 12:System.String 13:False 14:3 15: 16: 17:False 18:False 19:False 20: 21:False 22:False 23:System.Data.SqlTypes.SqlString 24:char 25: 26: 27: 28: 29:3
0:State 1:1 2:50 3:255 4:255 5:False 6: 7: 8: 9:State 10: 11: 12:System.String 13:False 14:22 15: 16: 17:False 18:False 19:False 20: 21:False 22:False 23:System.Data.SqlTypes.SqlString 24:varchar 25: 26: 27: 28: 29:22
0:CountryCode 1:2 2:2 3:255 4:255 5:False 6: 7: 8: 9:CountryCode 10: 11: 12:System.String 13:False 14:3 15: 16: 17:False 18:False 19:False 20: 21:False 22:False 23:System.Data.SqlTypes.SqlString 24:char 25: 26: 27: 28: 29:3
"
? datahelper.GetSchema("Trend")
"0:ColumnName 1:ColumnOrdinal 2:ColumnSize 3:NumericPrecision 4:NumericScale 5:IsUnique 6:IsKey 7:BaseServerName 8:BaseCatalogName 9:BaseColumnName 10:BaseSchemaName 11:BaseTableName 12:DataType 13:AllowDBNull 14:ProviderType 15:IsAliased 16:IsExpression 17:IsIdentity 18:IsAutoIncrement 19:IsRowVersion 20:IsHidden 21:IsLong 22:IsReadOnly 23:ProviderSpecificDataType 24:DataTypeName 25:XmlSchemaCollectionDatabase 26:XmlSchemaCollectionOwningSchema 27:XmlSchemaCollectionName 28:UdtAssemblyQualifiedName 29:NonVersionedProviderType
0:TrendID 1:0 2:4 3:10 4:255 5:False 6: 7: 8: 9:TrendID 10: 11: 12:System.Int32 13:False 14:8 15: 16: 17:True 18:True 19:False 20: 21:False 22:True 23:System.Data.SqlTypes.SqlInt32 24:int 25: 26: 27: 28: 29:8
0:Description 1:1 2:50 3:255 4:255 5:False 6: 7: 8: 9:Description 10: 11: 12:System.String 13:False 14:22 15: 16: 17:False 18:False 19:False 20: 21:False 22:False 23:System.Data.SqlTypes.SqlString 24:varchar 25: 26: 27: 28: 29:22
0:Length 1:2 2:4 3:10 4:255 5:False 6: 7: 8: 9:Length 10: 11: 12:System.Int32 13:False 14:8 15: 16: 17:False 18:False 19:False 20: 21:False 22:False 23:System.Data.SqlTypes.SqlInt32 24:int 25: 26: 27: 28: 29:8
"
Column 6 is IsKey but just displays 6: whereas IsIdentity displays correctly for Column 17. Can someone help me? Thanks in advance.
Found the problem. I need to use these command behavior values:
Dim drAs SqlDataReader = cmd.ExecuteReader(CommandBehavior.SchemaOnly + CommandBehavior.KeyInfo)
