Question

How can we explicitly convert data types in INSERT INTO/SELECT queries in MS Access?

Sample Query:

INSERT INTO pStudents( pStudentID, pDate, pRate, pGrade )
SELECT sStudentID, sDate, sRate, sGrade
FROM sStudents
WHERE (((sStudents.sStudentID) Is Not Null);

Here I want to convert fields from sStudents table before inserting in pStudents to following:

pStudentID = text
pDate = Short Date
pRate = Double
pGrade = text

Thanks in advance

Answer 1

You can use the built-in conversion functions of Access in the queries:

Select CStr(NumericColumn) from Table

…or as an INSERT query:

Insert Into AnotherTable (StringColumn)
Select CStr(NumericColumn) from Table

Did you mean something like that?

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EDIT:

Okay, your sample query with conversions would look like this:

INSERT INTO pStudents( pStudentID, pDate, pRate, pGrade )
SELECT CStr(sStudentID), CDate(sDate), CDbl(sRate), CStr(sGrade)
FROM sStudents
WHERE (((sStudents.sStudentID) Is Not Null);

However, this will only work if the columns contain only data that can actually be converted into the given type.

For example, you can convert a String column to Double with CDbl() – but only if the selected rows contain only values that can actually be converted into Double.
As soon as you select one row with a value that contains something else than numeric values (like ‘hello’), the conversion will fail.

On the other hand, do you really need the conversions?
Access can convert a lot by itself. For example, you can insert values from a numeric column into a string column, Access will convert it by itself. You don’t have to use CStr() for that.