PHP and MS Access: the number of records returned by a SELECT query

Question

I am running the following PHPcode to interact with an MS Access database.

$odbc_con = new COM("ADODB.Connection");
$constr = "DRIVER={Microsoft Access Driver (*.mdb)}; DBQ=" . $db_path . ";";
$odbc_con -> open($constr);

$rs_select = $odbc_con -> execute ("SELECT * FROM Main");

Usage ($rs_select -> RecordCount)gives -1, although the query returns non-zero entries.

(a) What is the reason? (b) Is there a way out?

I also tried to use count($rs_select -> GetRows()). This satisfies the need, but looks inefficient, since it involves first copying all the records into an array.

Answer 1

ADODB has its own rules by which a record is returned, depending on the type of record set that you define. Cm:

Knowledge Base Article 194973

W3C School Article

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Answer 2

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Answer 3

COUNT? :

$rs_select = $odbc_con -> execute ("SELECT COUNT(*) FROM Main");

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Answer 5

If you use the dynamic connection type with the cursor, it can really change. Someone may delete a record from this database while viewing record pages. To avoid this, use the static view of the snapshot cursor. I have this bookmark that will explain this well. It always called me, and the bookmark always reminded me why.

http://support.microsoft.com/kb/194973