DLookup：MS Access VBA中的查询与表？

Question

What is the difference between these two lines of code in MS Access VBA. does it really make a difference?

Facts:

1. tblLogin is a linked table
2. qryA is = tblLogin.*

-

DLookup("EmployeeID", "qryA", "[EmployeeID]=" & Me.empID) & "" = ""

vs

DLookup("EmployeeID", "tblLogin", "[EmployeeID]=" & Me.empID) & "" = ""

are there any restrictions that makes us want to go create a query identical to a table?

Answer 1

In DLookup? I've never encountered a difference. Pretty sure performance is the same. The advantages I can think of to using a query are unrelated to performance:

• Simplicity: if, for example, you later decide to have something like an "Active" flag in the table, and you want everything that references the table to filter out "inactive" records, you can just change the query.
• Security: this is more if the tables are in a linked server, but you may not want to reference the tables directly.

Answer 2

First of all, your question should say that you mean using DLookUp .

Second, in the case of DLookup, no, there is no difference.

But to be honest, just in that case. Queries are, with no doubt, more helpful to work with. Queries allow you to call for data in the way you want, sorted, with different parameters, grouping data (even from different tables).

To make it really simple, a table is like a store, where you save your goodies, and the query would be like a smart worker that gets for you in seconds the info the customer needs (or the boss), and this worker can adapt to any need.

That's my POV, anyways.