Dcount

Count the number of records in a table/query.

Syntax
      DCount ( expression, domain, [criteria] )

      =DCount("[Field]", "Table", "[Field] = 'MyValue'")

Key
   expression The field to count.

   domain     The set of records, a table or a query name.

   criteria   Equivalent to an (optional) WHERE clause.
              Any field that is included in criteria must
              also be a field in domain.

The DCount() function can be used in VBA or in an SQL query.

Examples

In a query:

In VBA:

DCount("OrderID", "T_Orders", "SupplierID = 64 ")

This is equivalent to:
SELECT DCount([T_Orders].OrderID)
FROM [T_Orders]
WHERE (([T_Orders].SupplierID)=64);

“If you are planning for a year, sow rice; if you are planning for a decade, plant trees; if you are planning for a lifetime, educate people” ~ Chinese Proverb

Related:

Count (SQL) - Count records
Nz - Detect a NULL value or Zero Length string.