Defining Filter Formulas; Filter Formula - SMC Networks EliteView 6.20 Management Manual

Defining Filter Formulas

Filters may be defined for any log process. A filter sets the conditions that determine if data received by the Log
Manager will be saved into the log database. A filter is defined in the Filter field of the Log Information dialog box
(i.e., the dialog box opened when you create or edit a log process). If no filter is defined, then all the data received
is automatically logged.

Filter Formula

The filter formula uses Backus-Naur Form (BNF) as follows:
Filter::=
SimpleExpression::=Variable rel_op Value
Variable::= "VALUE"|
rel_op::=
Value::=<INTEGER VALUE>|
ComplexExpression::=
"(" SimpleExpression ")" |
"(" ComplexExpression ")"|
ComplexExpression logic_op ComplexExpression
logic_op::="AND"|"OR"
SimpleExpression|
ComplexExpression|
<NULL>
--Value of the data
--Date the data arrives
"DATE"|
--Time the data arrives
"TIME"|
--Greater than
">"|
--Less than
"<"|
--Greater than or Equal to
">="|
--Less than or Equal to
"<="|
--Equal
"=="|
--Unequal
"!="|
--Number represented in decimal digits, within the range
--Eight digits representing a date
<yymmdd>|
--Eight digits representing a time, in 24 hour format
<hhmmss>
-- Nothing
of a 4-byte unsigned integer.
D F
EFINING
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F
ILTER ORMULAS
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