cursor.min()

Definition

cursor.min()

Important

mongosh Method

This page documents a mongosh method. This is not the documentation for a language-specific driver, such as Node.js.

For MongoDB API drivers, refer to the language-specific MongoDB driver documentation.

Specifies the inclusive lower bound for a specific index in order to constrain the results of find(). min() provides a way to specify lower bounds on compound key indexes.

The min() method has the following parameter:

Parameter	Type	Description
indexBounds	document	The inclusive lower bound for the index keys.

The indexBounds parameter has the following prototype form:

{ field1: <min value>, field2: <min value2>, fieldN:<min valueN> }

min() exists primarily to support the mongos process.

Behaviors

db.products.find( { $in: [ 6, 7 ] } ).min( { price: NumberDecimal("1.39") } ).hint( { price: 1 })

Example

Unless the find() query is an equality condition on the _id field { _id: <value> }, you must explicitly specify the index with the hint() method to run min().

For the examples below, create a sample collection named products that holds the following documents:

db.products.insertMany([
   { "_id" : 1, "item" : "apple", "type" : "honey crisp", "price" : NumberDecimal("1.99") },
   { "_id" : 2, "item" : "apple", "type" : "fuji", "price" : NumberDecimal("1.99") },
   { "_id" : 3, "item" : "apple", "type" : "jonagold", "price" : NumberDecimal("1.29") },
   { "_id" : 4, "item" : "apple", "type" : "jonathan", "price" : NumberDecimal("1.29") },
   { "_id" : 5, "item" : "apple", "type" : "mcintosh", "price" : NumberDecimal("1.29") },
   { "_id" : 6, "item" : "apple", "type" : "cortland", "price" : NumberDecimal("1.29") },
   { "_id" : 7, "item" : "orange", "type" : "cara cara", "price" : NumberDecimal("2.99") },
   { "_id" : 9, "item" : "orange", "type" : "satsuma", "price" : NumberDecimal("1.99") },
   { "_id" : 8, "item" : "orange", "type" : "valencia", "price" : NumberDecimal("0.99") },
   { "_id" : 10, "item" : "orange", "type" : "navel", "price" : NumberDecimal("1.39") }
])

Create the following indexes for the collection:

db.products.createIndexes( [
   { "item" : 1, "type" : 1 },
   { "item" : 1, "type" : -1 },
   { "price" : 1 }
] )

• Using the ordering of the { item: 1, type: 1 } index, min() limits the query to the documents that are at or above the index key bound of item equal to apple and type equal to jonagold, as in the following:

  db.products.find().min( { item: 'apple', type: 'jonagold' } ).hint( { item: 1, type: 1 } )

  The query returns the following documents:

  { "_id" : 3, "item" : "apple", "type" : "jonagold", "price" : NumberDecimal("1.29") }
  { "_id" : 4, "item" : "apple", "type" : "jonathan", "price" : NumberDecimal("1.29") }
  { "_id" : 5, "item" : "apple", "type" : "mcintosh", "price" : NumberDecimal("1.29") }
  { "_id" : 7, "item" : "orange", "type" : "cara cara", "price" : NumberDecimal("2.99") }
  { "_id" : 10, "item" : "orange", "type" : "navel", "price" : NumberDecimal("1.39") }
  { "_id" : 9, "item" : "orange", "type" : "satsuma", "price" : NumberDecimal("1.99") }
  { "_id" : 8, "item" : "orange", "type" : "valencia", "price" : NumberDecimal("0.99") }

• Using the ordering of the index { price: 1 }, min() limits the query to the documents that are at or above the index key bound of price equal to 1.39 and max() limits the query to the documents that are below the index key bound of price equal to 1.99:

  Note

  The bound specified by max() must be greater than the bound specified by min().

  db.products.find().min( { price: NumberDecimal("1.39") } ).max( { price:  NumberDecimal("1.99") } ).hint( { price: 1 } )

  The query returns the following documents:

  { "_id" : 10, "item" : "orange", "type" : "navel", "price" : NumberDecimal("1.39") }