Eduzan / NoSQL
Scalar Functions
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Description: Scalar functions in NoSQL databases perform operations on individual values and return a single result.
- Description: Converts a string to upper or lower case respectively.
- Example (MongoDB using
$toUpperand$toLowerin aggregation):
db.names.aggregate([{$project: {nameUpper: {$toUpper: "$name"}, nameLower: {$toLower: "$name"}}}]);Converts the name field of each document to upper and lower case.
- Description: Returns the length of a string.
- Example (MongoDB) :
db.names.aggregate([{$project: {nameLength: {$strLenCP: "$name"}}}]);Calculates the length of the name field for each document.
- Description: Rounds a number to the nearest integer or specified decimal place.
- Example (MongoDB) :
db.finances.aggregate([{$project: {roundedValue: {$round: ["$amount", 2]}}}]);Rounds the amount field to two decimal places.
End of lesson.