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Aliases: $match, $find

Filters the records to pass only the records that match the specified condition(s) to the next pipeline stage.

Stage as JSON

Single filter:

$filter: "blastid==160" // return only records where blastid equals 160

Multiple filters in stage:

// returns records where:
// (blastid equals 160) AND (segment equals 1 OR 2) AND (us_state equals "AK")
$filter: [
"segment in (1,2)",