About using the MSysConf table to optimize your linked SQL database

Important If you create an MSysConf table, it must be set up properly or you will not be able to connect to the SQL database table at all.

If you are administering an SQL database that uses Microsoft Access as a front end, then you can create a table in your SQL database named MSysConf to help you control communication between the two applications. The MSysConf table has two potential functions:

It can disable the feature that enables users to save the logon ID and password for a linked SQL database in the Microsoft Access front end.
It can optimize how Microsoft Access performs background population of records during idle time by setting the number of rows of data that are retrieved at one time and the number of seconds of delay between each retrieval. Microsoft Access uses a default of 100 records that are returned every 10 seconds if you don't create the MSysConf table.

The structure of the MSysConf table

The SQL database table MSysConf should have the following structure.

Column name	Data type	Allows Null?
Config	A data type that corresponds to a 2-byte integer	No
chValue	VARCHAR(255)	Yes
nValue	A data type that corresponds to a 4-byte integer	Yes
Comments	VARCHAR(255)	Yes

Note If the data source you're working with is case-sensitive, then use the table and column names exactly as shown.

The data in the MSysConf table

There are three valid records in the MSysConf table. The following table shows what values you should enter in the Config and nValue field. The other columns are reserved for future use, and their contents are ignored.

Config	nValue	Meaning
101	0	Don't allow local storage of the logon ID and password in linked tables.
101	1	Allow local storage of the logon ID and password in linked tables.
102	D	D is the delay in seconds between each retrieval.
103	N	N is the number of rows retrieved.

Note Setting a higher delay time decreases network traffic, but increases the amount of time that read-locks are left on data (if the server uses read-locks).