ALTER TABLE:使用默认值和复选框添加一个新的布尔列 [英] ALTER TABLE: Add a new boolean column with default value and checkbox

问题描述

将Boolean数据类型列添加到表中的正确Access DDL查询是什么?

What is the correct Access DDL query to add a Boolean datatype column to a table?

到目前为止，我已经看到了如下示例...

So far I've seen examples like the following...

ALTER TABLE MyTable ADD MyNewColumName BIT

但是自那以后，它们似乎并不是100％正确的

but they do not seem to be 100% correct since

1. Access不会将复选框控件应用于新添加的列，并且
2. 该列的允许值似乎是0和-1

推荐答案

DAO示例.

''Requires reference to Microsoft DAO 3.6 Object Library
Dim tdf As DAO.TableDef
Dim fld As DAO.Field
Dim db As Database
Dim strSQL As String


Set db = CurrentDb

''Create a table ...
strSQL = "Create Table tblLTD (TheYesNoCheck YesNo, TheYesNoCombo YesNo)"
db.Execute strSQL

''It is now in the table collection, so ...
Set tdf = db.TableDefs("tblLTD")

''Change the way the YesNo fields display.
''A Checkbox
Set fld = tdf.Fields("TheYesNoCheck")
Set prp = fld.CreateProperty("DisplayControl", dbInteger, acCheckBox)
fld.Properties.Append prp

''A combobox
Set fld = tdf.Fields("TheYesNoCombo")
Set prp = fld.CreateProperty("DisplayControl", dbInteger, acComboBox)
fld.Properties.Append prp
''We will need a format
Set prp = fld.CreateProperty("Format", dbText, "Yes/No")
fld.Properties.Append prp

来自: http://wiki.lessthandot.com/index. php/Add_a_Display_Control_(Checkbox，_Combobox)_to_a_YesNo_Field

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