6.1. Comparison Expressions
Comparison expressions match lines where if the condition is true, the action is performed. These expressions use relational operators and are used to compare numbers or strings. Table 6.1 provides a list of the relational operators. The value of the expression is 1 if the expression evaluates true, and 0 if false.
6.1.1. Relational Operators
| Operator | Meaning | Example |
|---|---|---|
| < | Less than. | x < y |
| <= | Less than or equal to. | x <= y |
| == | Equal to. | x == y |
| != | Not equal to. | x != y |
| >= | Greater than or equal to. | x >= y |
| > | Greater than. | x > y |
| ~ | Matched by regular expression. | x ~ /y/ |
| !~ | Not matched by regular expression. | x !~ /y/ |
Example 6.1.
(The Database) % cat employee Tom Jones 4423 5/12/66 543354 Mary ... |
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