The WHERE Clause

You can use the WHERE clause to narrow the scope of a query. The WHERE clause can contain a property or key word, an operator, and a constant. All WHERE clauses must specify one of the predefined WQL operators.

The basic syntax for appending the WHERE clause to the SELECT statement is:

SELECT instance FROM class WHERE expression

The expression is composed of a property or key word, an operator, and a constant. You can append the WHERE clause to the SELECT statement using one of the following forms:

SELECT instance FROM class [[WHERE property operator constant]]

SELECT instance FROM class [[WHERE constant operator property]]

Valid WHERE clauses follow these rules:

• The value of the constant must be of the correct data type for the property.

• The operator must be one of the valid WQL operators listed in Table 4–4.

• Either a property name or a constant must appear on either side of the operator in the WHERE clause.

• Arbitrary arithmetic expressions cannot be used. For example, the following query returns only instances of the Solaris_Printer class that represent a printer with ready status:

  SELECT * FROM Solaris_Printer WHERE Status = “ready”

  The following is an invalid query:

  SELECT * FROM PhysicalDisk WHERE Partitions < (8 + 2 - 2)

Multiple groups of properties, operators, and constants can be combined in a WHERE clause using logical operators and parenthetical expressions. Each group must be joined with the AND, OR, or NOT operators as shown in the following table.