ms access default value

Question

0.00/5 (No votes)

See more:

How can i add a fuction in 'default value' in field properties in ms access, to calculate the average of fields in the same table after a new record?

I try this but didn't work:

(([col1]+[col2]+[col3]+[col4])/4)

Please help.

Posted 7-Apr-13 3:33am

pouroutis

Updated 7-Apr-13 3:43am

v2

Add a Solution

2 solutions

Solution 2

AFAIK, you can't add any default value that is not known at compile time: when the data definition is saved. This means you can't use a calculated value that requires data from the row because that hasn't been set yet.

I would allow the field to be null, and work out the value using a stored procedure when I read it out - that way, the field value is also up-to-date if no value has been specified. Your way would only set the default once based on the initial values which may be well different to the actual value when you read them.

Posted 7-Apr-13 4:02am

OriginalGriff

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Maciej Los · Accepted Answer · 2013-04-07T03:55:00

Some useful information you'll find here: http://office.microsoft.com/en-us/access-help/set-a-default-value-for-a-field-or-control-mdb-HP005188852.aspx[^]

You don't need to set default value for field in database table, because, you can always set "default value" in query:

SQL

PARAMETERS p1 INT, p2 INT, p3 INT, p4 INT;
INSERT INTO YourTable (col1, col2, col3, col4, col5)
VALUES(p1, p2, p3, p4, (p1+p2+p3+p4)/4);

But i'm wondering why do you want to store average value, if you always can calculate it (based on col1-col4 values)?

SQL

SELECT col1, col2, col3, col4, (col1+col2+col3+col4)/4 AS col5
FROM YourTable