MongoDB simple to use-query operation 3

First add a few documents:

DVD = ({"Type": "DVD", "Title": "Matrix,the", "released": 1994, "Cast": ["Keanu Reeves", "Carrie-anne Moss", "Laurence Fishburne "," Hugo Weaving "," Gloria Foster "," Joe Pantoliano "]})

Db.media.insertOne (DVD)

DVD = ({"Type": "DVD", "Title": "Blade Runner", "released": 1982})
Db.media.insertOne (DVD)

DVD = ({"Type": "DVD", "Title": "Toy Story 3", "Released": 2010})

Db.media.insertOne (DVD)

1. Compare symbols ($GT, $gte, $lt, $lte) # (greater than, greater than, equal to, less than, less than or equal to)

Db.media.find ({released:{$gt: 2000}},{"Cast": 0})

System returns
{"_id": ObjectId ("5aa4984153350e04ddbd6fab"), "Type": "DVD", "Title": "Toy Story 3", "Released": 2010}

Db.media.find ({released:{$gte: 1994, $lt: 2010}},{"Cast": 0})

System returns
{"_id": ObjectId ("5aa497c753350e04ddbd6fa9"), "Type": "DVD", "Title": "Matrix,the", "released": 1994}

2. $in, $all, $or

Db.media.find ({released:{$in: [1994,2008,2009]}},{"Cast": 0}

System returns

{"_id": ObjectId ("5aa497c753350e04ddbd6fa9"), "Type": "DVD", "Title": "Matrix,the", "released": 1994}

Db.media.find ({released:{$all: [1994,2008,2009]}},{"Cast": 0})

System returns

(There is no document that satisfies 3 conditions at the same time, returns null)

Db.media.find ({$or: [{"Title": "Toy Story 3"},{"ISBN": "978-1-4842-1183-0"}]})

System returns
{"_id": ObjectId ("5aa490f053350e04ddbd6fa6"), "Type": "Book", "Title": "Definitive Guide to MongoDB 3rd ed.", "ISBN": "978-1-4842-1183-0", "Publisher": "Apress", "Author": ["Hows,david", "Plugge,eelco", "Membrey,peter", "Hawkins,tim"] }

3. $slice

Db.media.find ({"Title": "Matrix,the"},{"Cast": {$slice: 3}})

System returns
{"_id": ObjectId ("5aa497c753350e04ddbd6fa9"), "Type": "DVD", "Title": "Matrix,the", "released": 1994, "Cast": ["Kea Nu Reeves "," Carrie-anne Moss "," Laurence Fishburne "]}

Db.media.find ({"Title": "Matrix,the"},{"Cast": {$slice: [ -5,4]}}) #从最后5项中截取前4个

System returns
{"_id": ObjectId ("5aa497c753350e04ddbd6fa9"), "Type": "DVD", "Title": "Matrix,the", "released": 1994, "Cast": ["Car Rie-anne Moss "," Laurence Fishburne "," Hugo Weaving "," Gloria Foster "]}

4. $mod

Db.media.find ({released:{$mod: [3,2]}},{"Cast": 0})

System returns:

{"_id": ObjectId ("5aa497c753350e04ddbd6fa9"), "Type": "DVD", "Title": "Matrix,the", "released": 1994}
{"_id": ObjectId ("5aa4981653350e04ddbd6faa"), "Type": "DVD", "Title": "Blade Runner", "released": 1982}

5. $size

Db.media.find ({tracklist:{$size: 2}})

System returns:
{"_id": ObjectId ("5aa4912953350e04ddbd6fa7"), "Type": "CD", "Artist": "Nirvana", "Title": "Nevermind", "tracklist": [{' track ': ' 1 ', ' title ': ' Smells like Teen Spirit ', ' Length ': ' 5:02 '}, {' track ': ' 2 ', ' title ': ' In Bloom ', ' lengt H ":" 4:15 "}]}

6. $exists

Db.media.find ({author:{$exists: true}})

System returns:
{"_id": ObjectId ("5aa490f053350e04ddbd6fa6"), "Type": "Book", "Title": "Definitive Guide to MongoDB 3rd ed.", "ISBN": "978-1-4842-1183-0", "Publisher": "Apress", "Author": ["Hows,david", "Plugge,eelco", "Membrey,peter", "Hawkins,tim"] }
{"_id": ObjectId ("5aa4915453350e04ddbd6fa8"), "Type": "Book", "Title": "Definitive Guide to MongoDB 3rd ed.", "ISBN": "978-1-4842-1183-1", "Publisher": "Apress", "Author": ["Hows,david", "Plugge,eelco", "Membrey,peter", "Hawkins,tim"] }

Db.media.find ({author:{$exists: false}})

System returns:
{"_id": ObjectId ("5aa4912953350e04ddbd6fa7"), "Type": "CD", "Artist": "Nirvana", "Title": "Nevermind", "tracklist": [{' track ': ' 1 ', ' title ': ' Smells like Teen Spirit ', ' Length ': ' 5:02 '}, {' track ': ' 2 ', ' title ': ' In Bloom ', ' lengt H ":" 4:15 "}]}
{"_id": ObjectId ("5aa497c753350e04ddbd6fa9"), "Type": "DVD", "Title": "Matrix,the", "released": 1994, "Cast": ["Kea Nu Reeves "," Carrie-anne Moss "," Laurence Fishburne "," Hugo Weaving "," Gloria Foster "," Joe Pantoliano "]}
{"_id": ObjectId ("5aa4981653350e04ddbd6faa"), "Type": "DVD", "Title": "Blade Runner", "released": 1982}
{"_id": ObjectId ("5aa4984153350e04ddbd6fab"), "Type": "DVD", "Title": "Toy Story 3", "Released": 2010}

7. $type

Db.media.find ({tracklist:{$type: 3}}) #type: 3 for embedded objects
{"_id": ObjectId ("5aa4912953350e04ddbd6fa7"), "Type": "CD", "Artist": "Nirvana", "Title": "Nevermind", "tracklist": [{' track ': ' 1 ', ' title ': ' Smells like Teen Spirit ', ' Length ': ' 5:02 '}, {' track ': ' 2 ', ' title ': ' In Bloom ', ' lengt H ":" 4:15 "}]}

8. $elemMatch

Db.media.find ({"Tracklist.title": "Smells like Teen Spirit", "Tracklist.track": "1"})

System returns:
{"_id": ObjectId ("5aa4912953350e04ddbd6fa7"), "Type": "CD", "Artist": "Nirvana", "Title": "Nevermind", "tracklist": [{' track ': ' 1 ', ' title ': ' Smells like Teen Spirit ', ' Length ': ' 5:02 '}, {' track ': ' 2 ', ' title ': ' In Bloom ', ' lengt H ":" 4:15 "}]}
{"_id": ObjectId ("5aa49fe653350e04ddbd6fac"), "Type": "CD", "Artist": "Nirvana", "Title": "Nirvana", "tracklist": [ {' track ': ' 1 ', ' title ': ' You Know ' is right ', ' Length ': ' 3:38 '}, {' track ': ' 5 ', ' title ': ' Smells like Teen Spi Rit "," Length ":" 5:02 "}]}

Db.media.find ({tracklist:{$elemMatch: {Title: ' Smells like Teen Spirit ', Track: ' 1 '}}})

System returns:
{"_id": ObjectId ("5aa4912953350e04ddbd6fa7"), "Type": "CD", "Artist": "Nirvana", "Title": "Nevermind", "tracklist": [{' track ': ' 1 ', ' title ': ' Smells like Teen Spirit ', ' Length ': ' 5:02 '}, {' track ': ' 2 ', ' title ': ' In Bloom ', ' lengt H ":" 4:15 "}]}

9. Regular expressions

Db.media.find ({title:/^matrix*/i}) #i表示不区分大小写

System returns:
{"_id": ObjectId ("5aa497c753350e04ddbd6fa9"), "Type": "DVD", "Title": "Matrix,the", "released": 1994, "Cast": ["Kea Nu Reeves "," Carrie-anne Moss "," Laurence Fishburne "," Hugo Weaving "," Gloria Foster "," Joe Pantoliano "]}

MongoDB simple to use-query operation 3