getinfo.frm

《VB6数据库开发指南》所有的例程的源码

                    SpecialStr = "Partial outer joins."
                Case "F"
                    SpecialStr = "Full outer joins."
                Case Else
                    SpecialStr = "Missing data."
            End Select
        Case "SQL_NEED_LONG_DATA_LEN"
            SpecialStr = IIf(RetStr = "Y", "Yes", "No")
        Case "SQL_LIKE_ESCAPE_CLAUSE"
            SpecialStr = IIf(RetStr = "Y", "Yes", "No")
        Case "SQL_ACCESSIBLE_PROCEDURES"
            SpecialStr = IIf(RetStr = "Y", "Yes", "No")
        Case "SQL_ACCESSIBLE_TABLES"
            SpecialStr = IIf(RetStr = "Y", "Yes", "No")
        Case "SQL_DATA_SOURCE_READ_ONLY"
            SpecialStr = IIf(RetStr = "Y", "Yes", "No")
        Case "SQL_PROCEDURES"
            SpecialStr = IIf(RetStr = "Y", "Yes", "No")
        Case "SQL_ROW_UPDATES"
            SpecialStr = IIf(RetStr = "Y", "Yes", "No")
        Case Else
            SpecialStr = "Missing special processing."
    End Select
End Function
Private Function SpecialInt(Opt As String, RetInt As Integer)
    'Do any special processing required for a SQLGetInfo integer
    Select Case Opt
        Case "SQL_CORRELATION_NAME"
            Select Case RetInt
                Case SQL_CN_NONE
                    SpecialInt = "Not supported."
                Case SQL_CN_DIFFERENT
                    SpecialInt = "Supported but names vary."
                Case SQL_CN_ANY
                    SpecialInt = "Any valid user name."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_NON_NULLABLE_COLUMNS"
            Select Case RetInt
                Case SQL_NNC_NULL
                    SpecialInt = "All columns nullable."
                Case SQL_NNC_NON_NULL
                    SpecialInt = "May be non-nullable."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_FILE_USAGE"
            Select Case RetInt
                Case SQL_FILE_NOT_SUPPORTED
                    SpecialInt = "Not a single tier driver."
                Case SQL_FILE_TABLE
                    SpecialInt = "Treats data source as table."
                Case SQL_FILE_QUALIFIER
                    SpecialInt = "Treats data source as qualifier."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_NULL_COLLATION"
            Select Case RetInt
                Case SQL_NC_END
                    SpecialInt = "NULLs sorted to end."
                Case SQL_NC_HIGH
                    SpecialInt = "NULLs sorted to high end."
                Case SQL_NC_LOW
                    SpecialInt = "NULLs sorted to low end."
                Case SQL_NC_START
                    SpecialInt = "NULLs sorted to start."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_GROUP_BY"
            Select Case RetInt
                Case SQL_GB_NOT_SUPPORTED
                    SpecialInt = "Group By not supported."
                Case SQL_GB_GROUP_BY_EQUALS_SELECT
                    SpecialInt = "All non-aggregated columns, no others."
                Case SQL_GB_GROUP_BY_CONTAINS_SELECT
                    SpecialInt = "All non-aggregated columns, some others."
                Case SQL_GB_NO_RELATION
                    SpecialInt = "Not related to select list."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_IDENTIFIER_CASE"
            Select Case RetInt
                Case SQL_IC_UPPER
                    SpecialInt = "Upper case."
                Case SQL_IC_LOWER
                    SpecialInt = "Lower case."
                Case SQL_IC_SENSITIVE
                    SpecialInt = "Case sensitive."
                Case SQL_IC_MIXED
                    SpecialInt = "Mixed case."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_QUOTED_IDENTIFIER_CASE"
            Select Case RetInt
                Case SQL_IC_UPPER
                    SpecialInt = "Upper case."
                Case SQL_IC_LOWER
                    SpecialInt = "Lower case."
                Case SQL_IC_SENSITIVE
                    SpecialInt = "Case sensitive."
                Case SQL_IC_MIXED
                    SpecialInt = "Mixed case."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_ODBC_API_CONFORMANCE"
            Select Case RetInt
                Case SQL_OAC_NONE
                    SpecialInt = "No conformance."
                Case SQL_OAC_LEVEL1
                    SpecialInt = "Level 1 supported."
                Case SQL_OAC_LEVEL2
                    SpecialInt = "Level 2 supported."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_CURSOR_COMMIT_BEHAVIOR"
            Select Case RetInt
                Case SQL_CB_DELETE
                    SpecialInt = "Close and delete statements."
                Case SQL_CB_CLOSE
                    SpecialInt = "Close cursors."
                Case SQL_CB_PRESERVE
                    SpecialInt = "Preserve cursors."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_CURSOR_ROLLBACK_BEHAVIOR"
            Select Case RetInt
                Case SQL_CB_DELETE
                    SpecialInt = "Close and delete statements."
                Case SQL_CB_CLOSE
                    SpecialInt = "Close cursors."
                Case SQL_CB_PRESERVE
                    SpecialInt = "Preserve cursors."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_TXN_CAPABLE"
            Select Case RetInt
                Case SQL_TC_NONE
                    SpecialInt = "Transactions not supported."
                Case SQL_TC_DML
                    SpecialInt = "DML statements only, DDL cause error."
                Case SQL_TC_DDL_COMMIT
                    SpecialInt = "DML statements, DDL commit transaction."
                Case SQL_TC_DDL_IGNORE
                    SpecialInt = "DML statements, DDL ignored."
                Case SQL_TC_ALL
                    SpecialInt = "Both DML and DDL statements."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_QUALIFIER_LOCATION"
            Select Case RetInt
                Case SQL_QL_START
                    SpecialInt = "Start of name."
                Case SQL_QL_END
                    SpecialInt = "End of name."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case "SQL_CONCAT_NULL_BEHAVIOR"
            Select Case RetInt
                Case SQL_CB_NULL
                    SpecialInt = "intResult is NULL valued."
                Case SQL_CB_NON_NULL
                    SpecialInt = "intResult is non-NULL concatenation."
                Case Else
                    SpecialInt = "Missing data."
            End Select
        Case Else
            SpecialInt = "Missing special integer processing."
    End Select
End Function
Private Function BitMask(RetBit As Long)
    'Do processing required for a SQLGetInfo bit mask return
      Dim I As Long, bin As String
      Const maxpower = 30   ' Maximum number of binary digits supported.
      bin = ""  'Build the desired binary number in this string, bin.
      
      If RetBit > 2 ^ maxpower Then
         BitMask = "Error converting data."
         Exit Function
      End If

      ' Negative numbers have "1" in the 32nd left-most digit:
      If RetBit < 0 Then bin = bin + "1" Else bin = bin + "0"

      For I = maxpower To 0 Step -1
         If RetBit And (2 ^ I) Then   ' Use the logical "AND" operator.
            bin = bin + "1"
         Else
            bin = bin + "0"
         End If
      Next
      BitMask = bin ' The bin string contains the binary number.
End Function
Private Function SpecialLong(Opt As String, RetInt As Integer)
    'Do any special processing required for a SQLGetInfo long
    Select Case Opt
        Case "SQL_DEFAULT_TXN_ISOLATION"
            Select Case RetInt
                Case SQL_TXN_READ_UNCOMMITTED
                    SpecialLong = "Dirty reads, nonrepeatable, phantoms."
                Case SQL_TXN_READ_COMMITTED
                    SpecialLong = "No dirty reads, but nonrepeatable and phantoms."
                Case SQL_TXN_REPEATABLE_READ
                    SpecialLong = "No dirty or nonrepeatable reads. Phantoms okay."
                Case SQL_TXN_SERIALIZABLE
                    SpecialLong = "Serializable transactions."
                Case SQL_TXN_VERSIONING
                    SpecialLong = "Serializable transactions with higher concurrency."
                Case Else
                    SpecialLong = "Missing data."
            End Select
              
        Case Else
            SpecialLong = "Missing special Long processing."
    End Select
End Function