'★ 注意,本测试是由文章 ' 《数据定义查询不会怎么办?》 ' http://access911.net/?kbid;71FAB01E15DC ' 中 “dd autoincrement guid ”的描述引发的,当时写上述文章的环境可能是 OFFICE 2000 ,现在 ' 我没有此环境无法测试,暂时先把本次测试的结果记录下来 ' 本次测试还关联到一篇文章代码的正确性,请大家认真参考一下 ' 《如何根据当前MDB中的表生成对应的JET SQL DDL “CREATE TABLE”语句/脚本?》 ' http://access911.net/?kbid;72FAB11E16DCEBF3 ' 上述文章中有关 DDL 建立 自动编号 GUID 部分的代码需要更改 ' 为便于区分,打 ★ 的代码是与本测试直接相关的代码,其他为辅助代码
'★ -- test #1 start 'Please copy these code in VBA module and press F5 to run the follow function '请将以下代码 COPY 到 VBA 模块中,然后按 F5 键运行以下两段函数 Function RunTest_CreateScript() CreateSQLString "c:\temp.jetsql" End Function '★ -- test #1 end
'★ 以下是 Debug.Print 出来的结果,大家可以明显看出不同,我用 ☆ 将不同点标出 ' 表1:aa 字段,自动编号 长整 递增; ' 表2:bb 字段,自动编号 长整 随机; ' 表3:cc 字段,自动编号 GUID ' ' ---------- aa 自动编号 长整 递增; ---------- '☆ Autoincrement True '☆ Default ' Description ' Nullable True ' Fixed Length True ' Seed 1 ' Increment 1 ' Jet OLEDB:Column Validation Text ' Jet OLEDB:Column Validation Rule ' Jet OLEDB:IISAM Not Last Column False '☆ Jet OLEDB: AutoGenerate False ' Jet OLEDB:One BLOB per Page False ' Jet OLEDB:Compressed UNICODE Strings False ' Jet OLEDB:Allow Zero Length False ' Jet OLEDB: Hyperlink False ' ---------- bb 自动编号 长整 随机; ---------- '☆ Autoincrement True '☆ Default GenUniqueID() ' Description ' Nullable True ' Fixed Length True ' Seed 1 ' Increment 1 ' Jet OLEDB:Column Validation Text ' Jet OLEDB:Column Validation Rule ' Jet OLEDB:IISAM Not Last Column False '☆ Jet OLEDB: AutoGenerate False ' Jet OLEDB:One BLOB per Page False ' Jet OLEDB:Compressed UNICODE Strings False ' Jet OLEDB:Allow Zero Length False ' Jet OLEDB: Hyperlink False ' ---------- cc 自动编号 GUID ---------- '☆ Autoincrement False '☆ Default GenGUID() ' Description ' Nullable True ' Fixed Length True ' Seed 1 ' Increment 1 ' Jet OLEDB:Column Validation Text ' Jet OLEDB:Column Validation Rule ' Jet OLEDB:IISAM Not Last Column False '☆ Jet OLEDB: AutoGenerate True ' Jet OLEDB:One BLOB per Page False ' Jet OLEDB:Compressed UNICODE Strings False ' Jet OLEDB:Allow Zero Length False ' Jet OLEDB: Hyperlink False
Function CreateSQLString(ByVal FilePath As String) As Boolean
'本函数根据当前MDB中的表创建一个 *.jetsql 脚本 '这个函数不是最完美的解决方案,因为 JET SQL DDL 语句不支持一些 ACCESS 特有的属性(DAO支持) 'This function create a "*.jetsql" script based on current mdb tables. 'This function is not the BEST, because the JET SQL DDL never support some DAO property.
Dim MyTableName As String Dim MyFieldName As String Dim MyDB As New ADOX.Catalog Dim MyTable As ADOX.Table Dim MyField As ADOX.Column Dim pro Dim iC As Long Dim strField() As String Dim strKey As String Dim strSQL As String Dim strSQLScript As String Dim objFile, stmFile Dim strText As String
On Error GoTo CreateSQLScript_Err MyDB.ActiveConnection = CurrentProject.Connection For Each MyTable In MyDB.Tables If MyTable.Type = "TABLE" Then '指定表的类型,例如“TABLE”、“SYSTEM TABLE”或“GLOBAL TEMPORARY”或者“ACCESS TABLE”。 'ADOX 无法判断该表是否已经被删除,还有两种方式判断, '方法一:(用 DAO) 'If CurrentDb.TableDefs(strTableName).Attributes = 0 Then '方法二:(在判断 ADOX.Table.Type 的基础上再判定表名) 'If Left(MyTable.Name, 7) <> "~TMPCLP" Then strSQL = "create table [" & MyTable.Name & "](" For Each MyField In MyTable.Columns ReDim Preserve strField(iC) strField(iC) = SQLField(MyField) iC = iC + 1 Next strSQL = strSQL & Join(strField, ",") '获取当前表的字段信息后立即重新初始化 strField 数组 iC = 0 ReDim strField(iC) '加入键信息 strKey = SQLKey(MyTable) If Len(strKey) <> 0 Then strSQL = strSQL & "," & strKey End If strSQL = strSQL & ");" & vbCrLf strSQLScript = strSQLScript & strSQL 'Debug.Print SQLIndex(MyTable) 'Never support the INDEX,to be continued... '暂未支持 index 脚本,未完待续... End If Next Set MyDB = Nothing
'create the Jet SQL Script File Set objFile = CreateObject("Scripting.FileSystemObject") Set stmFile = objFile.CreateTextFile(FilePath, True) stmFile.Write strSQLScript stmFile.Close Set stmFile = Nothing Set objFile = Nothing
CreateSQLScript = True
CreateSQLScript_Exit: Exit Function
CreateSQLScript_Err: MsgBox Err.Description, vbExclamation CreateSQLScript = False Resume CreateSQLScript_Exit
End Function
Function RunFromText(ByVal FilePath As String) '本函数将 CreateSQLScript 生成的 *.jetsql 脚本来生成 mdb 数据库中的表 'This Function run the "*.jetsql" which is created by CreateSQLScript to create the tables in current mdb database. On Error Resume Next Dim objFile, stmFile Dim strText As String Set objFile = CreateObject("Scripting.FileSystemObject") Set stmFile = objFile.OpenTextFile(FilePath, 1, False) strText = stmFile.ReadAll stmFile.Close Set stmFile = Nothing Set objFile = Nothing Dim strSQL() As String Dim i As Long strSQL = Split(strText, ";" & vbCrLf) For i = LBound(strSQL) To UBound(strSQL) CurrentProject.Connection.Execute Trim(strSQL(i)) If Err <> 0 Then Debug.Print "Error SQL is:" & strSQL(i) Err.Clear End If Next End Function
Function SQLKey(ByVal objTable As ADOX.Table) '调用 ADOX 生成有关“键”的 JET SQL DDL 子句 'Reference ADOX and create the JET SQL DDL clause about the "Key"
Dim MyKey As ADOX.Key Dim MyKeyColumn As ADOX.Column Dim strKey As String Dim strColumns() As String Dim strKeys() As String Dim i As Long Dim iC As Long For Each MyKey In objTable.Keys Select Case MyKey.Type Case adKeyPrimary strKey = "Primary KEY " Case adKeyForeign strKey = "FOREIGN KEY " Case adKeyUnique strKey = "UNIQUE " End Select For Each MyKeyColumn In MyKey.Columns ReDim Preserve strColumns(iC) strColumns(iC) = "[" & MyKeyColumn.Name & "]" iC = iC + 1 Next ReDim Preserve strKeys(i) strKeys(i) = strKey & "(" & Join(strColumns, ",") & ")" '获取信息后,立即初始化数组 iC = 0 ReDim strColumns(iC) i = i + 1 Next SQLKey = Join(strKeys, ",") End Function
Function SQLField(ByVal objField As ADOX.Column) '调用 ADOX 生成有关“字段”的 JET SQL DDL 子句 'Reference ADOX and create the JET SQL DDL clause about the "Field"
Dim p As String Select Case objField.Type Case 11 p = " yesno" Case 6 p = " money" Case 7 p = " datetime" Case 5 p = " FLOAT" 'or " Double" Case 72 If objField.Properties("Autoincrement") = True Then p = " autoincrement GUID" Else p = " GUID" End If Case 3 If objField.Properties("Autoincrement") = False Then p = " smallint" Else p = " AUTOINCREMENT(1," & objField.Properties("Increment") & ")" End If Case 205 p = " image" Case 203 p = " memo" 'Access "HyperLink" field is also a MEMO data type. 'ACCESS 的超级链接也是 MEMO 类型的 Case 131 p = " DECIMAL" p = p & "(" & objField.Precision & ")" Case 4 p = " single" 'or " REAL" Case 2 p = " smallint" Case 17 p = " byte" Case 202 p = " nvarchar" p = p & "(" & objField.DefinedSize & ")" Case Else p = " (Unknown,You can find it in ADOX's help. Please Check it.)" End Select p = "[" & objField.Name & "]" & p If IsEmpty(objField.Properties("Default")) = False Then p = p & " default " & objField.Properties("Default") End If If objField.Properties("Nullable") = False Then p = p & " not null" End If '★ -- test #2 start '这里让我们来监测一下自动编号字段和GUID字段的不同吧 '注意,在做这个测试时必须手动创建三个表,每个表都只包含一个自动编号字段, '表1:aa 字段,自动编号 长整 递增; '表2:bb 字段,自动编号 长整 随机; '表3:cc 字段,自动编号 GUID Dim bbb Debug.Print String(10, "-"), objField.Name, String(10, "-") For Each bbb In objField.Properties Debug.Print bbb.Name, bbb.Value Next '★ -- test #2 end SQLField = p End Function
Function RunTest_RunScript() delAllTable RunFromText "c:\temp.jetsql" End Function
Function delAllTable() '在生成新表时先删除数据库中所有的表 'Delete all table in current mdb. On Error Resume Next Dim t As New TableDef For Each t In CurrentDb.TableDefs If t.Attributes = 0 Then CurrentProject.Connection.Execute "drop table [" & t.Name & "]" End If Next End Function
Function CreateEGTable() CurrentProject.Connection.Execute "create table [表e2]([ID] AUTOINCREMENT(1,1),[URL] memo,[备注] memo,[长整] smallint default 0,[大二进制] image,[日期] datetime,[数字同步复制ID] GUID,[数字字节] byte default 0,[文本50UNICODE关] nvarchar(50),[文本50UNICODE开] nvarchar(50),[文本50必填是允许空否] nvarchar(50) not null,[小数精度18] DECIMAL(10) default 0,Primary KEY ([ID]))" End Function
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