In MongoDB, the $range aggregation pipeline operator returns a generated sequence of numbers in an array.
This sequence of numbers is based on the input values you provide.
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MongoDB $round
In MongoDB, the $round aggregation pipeline operator rounds a number to a whole integer or to a specified decimal place.
You have the option of specifying how many decimal places for which to round the number. To do this, pass a second argument. The first argument is the number to round, and the second (optional) argument is the number of decimal places to round it to.
Continue readingMongoDB $sample
In MongoDB, the $sample aggregation pipeline stage randomly selects the specified number of documents from its input.
MongoDB $rand
In MongoDB, the $rand aggregation pipeline operator returns a random float between 0 and 1.
The floating point value has up to 17 digits after the decimal point. Any trailing zeros are dropped, so the number of digits may vary.
The $rand operator was introduced in MongoDB 4.4.2.
MongoDB $nin Query Operator
In MongoDB, the $nin query operator selects the documents where the field’s value is not in the specified array or where the field doesn’t exist.
MongoDB $ne Aggregation Pipeline Operator
In MongoDB, the $ne aggregation pipeline operator compares two values and returns either true or false, depending on whether the two values are not equivalent.
MongoDB $in Aggregation Pipeline Operator
In MongoDB, the $in aggregation pipeline operator returns a boolean indicating whether a specified value is in the array.
The $in aggregation pipeline operator is not to be confused with the $in query operator, which selects the documents where the value of a field equals any value in the specified array.
MongoDB $in Query Operator
In MongoDB, the $in query operator selects the documents where the value of a field equals any value in the specified array.
The $in query operator is not to be confused with the $in aggregation pipeline operator, which returns a boolean indicating whether a specified value is in the array.
MongoDB $gte Aggregation Pipeline Operator
In MongoDB, the $gte aggregation pipeline operator compares two values and returns either true or false, depending on whether or not the first value is greater than or equal to the second value.
MongoDB $ifNull
In MongoDB, $ifNull is an aggregation pipeline operator that allows you to specify a value to use in place of null.
The way that it works is, you provide an expression and a replacement expression. If the expression evaluates to a non-null value, that expression is returned. But if the expression evaluates to a null value, $ifNull returns the value of the replacement expression.
A null value includes instances of undefined values or missing fields.
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