filter-rows-on.md

Filter Rows On

The FILTER-ROWS-ON directive filters records based on a condition.

Syntax

filter-rows-on <filter-type> <options>

The <filter-type> specifies the type of filter used and the options to be supplied to it.

Supported filter types and their options:

condition-false <boolean-expression>
condition-true <boolean-expression>
empty-or-null-columns <column>[,<column>]*
regex-match <regular-expression>
regex-not-match <regular-expression>

Usage Notes

The FILTER-ROWS-ON directive applies the filter type and a boolean or regular expression on a column value for each record. If the expression matches or returns true for the column value, then the record is omitted; otherwise, it is passed on as-is to the input of the next directive.

Note that it is a combination of the <filter-type> and the options. For instance, if condition-true is used and its <boolean-expression> evaluates to true, then the row will be omitted and not passed on.

Examples

Using this record as an example:

{
  "id": 1,
  "name": "Joltie, Root",
  "emailid": "[email protected]",
  "hrlywage": 12.34,
  "gender": "Male",
  "country": "US"
}

Applying this directive:

filter-rows-on condition-true country !~ 'US'

would result in filtering out records for individuals that are not in the US (where country does not match "US").

Applying this directive:

filter-rows-on condition-true (country !~ 'US' && hrlywage > 12)

would result in filtering out records for individuals that are not in the US (where country does not match "US") and whose hourly wage (hrlywage) is greater than 12.