0
> db.inventory.find()
{ "_id" : ObjectId("5eb67598bee5213484d45087"), "item" : "journal", "qty" : 25, "status" : "A", "size" : { "h" : 14, "w" : 21, "uom" : "cm" }, "tags" : [ "blank", "red" ] }
{ "_id" : ObjectId("5eb67598bee5213484d45088"), "item" : "notebook", "qty" : 50, "status" : "A", "size" : { "h" : 8.5, "w" : 11, "uom" : "in" }, "tags" : [ "red", "blank" ] }
{ "_id" : ObjectId("5eb67598bee5213484d45089"), "item" : "paper", "qty" : 10, "status" : "D", "size" : { "h" : 8.5, "w" : 11, "uom" : "in" }, "tags" : [ "red", "blank", "plain" ] }
{ "_id" : ObjectId("5eb67598bee5213484d4508a"), "item" : "planner", "qty" : 0, "status" : "D", "size" : { "h" : 22.85, "w" : 30, "uom" : "cm" }, "tags" : [ "blank", "red" ] }
{ "_id" : ObjectId("5eb67598bee5213484d4508b"), "item" : "postcard", "qty" : 45, "status" : "A", "size" : { "h" : 10, "w" : 15.25, "uom" : "cm" }, "tags" : [ "blue" ] }
{ "_id" : ObjectId("5ebfd02b3a3b38a52be04608"), "item" : "journal", "qty" : 25, "tags" : [ "blank", "red" ], "dim_cm" : [ 14, 21 ] }
{ "_id" : ObjectId("5ebfd02b3a3b38a52be04609"), "item" : "notebook", "qty" : 50, "tags" : [ "red", "blank" ], "dim_cm" : [ 14, 21 ] }
{ "_id" : ObjectId("5ebfd02b3a3b38a52be0460a"), "item" : "paper", "qty" : 100, "tags" : [ "red", "blank", "plain" ], "dim_cm" : [ 14, 21 ] }
{ "_id" : ObjectId("5ebfd02b3a3b38a52be0460b"), "item" : "planner", "qty" : 75, "tags" : [ "blank", "red" ], "dim_cm" : [ 22.85, 30 ] }
{ "_id" : ObjectId("5ebfd02b3a3b38a52be0460c"), "item" : "postcard", "qty" : 45, "tags" : [ "blue" ], "dim_cm" : [ 10, 15.25 ] }

Both of the following queries are resulting in nothing:

> db.inventory.find( { size: { h: { $gt: 14 } }  } )
> 
> db.inventory.find( { size: { $elemMatch: {  h: { $gt: 14 } } } } )

Whereas there is a document greater than 14: 

{ "_id" : ObjectId("5eb67598bee5213484d4508a"), "item" : "planner", "qty" : 0, "status" : "D", "size" : { "h" : 22.85, "w" : 30, "uom" : "cm" }, "tags" : [ "blank", "red" ] }

Following syntax doesn't work: > db.inventory.find( { size.h: { $gt: 14 } } )
2020-05-24T15:08:44.306+0530 E QUERY [js] uncaught exception: SyntaxError: missing : after property id :@(shell):1:25 `

Please explain why.

Aquarius_Girl
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1 Answers1

2

You need to add dot notation while querying nested documents. Can you try this

db.inventory.find( { 'size.h': { $gt: 14 } } )
vishnu
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