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Update MongoDB field using value of another field

MongoDB: Updating documents using data from the same documentUpdate field with another field's value in the documentMongoDB : how to set a new field equal to the value of another field, for every document in a collectionMongoose findOneAndUpdate - update one field using anotherHow to update a field using its previous value in MongoDB/MongoosePyMongo - Setting all values in an attribute to lowercaseupdate field with existing field in mongodbUpdate specific field in all documents in MongoDBAdd new field which is the size of another field of the documentmongodb update query to append a data to already existing fieldHow do I perform the SQL Join equivalent in MongoDB?Update field with another field's value in the documentMongoDB vs. CassandraHow to query MongoDB with “like”?Retrieve only the queried element in an object array in MongoDB collectionHow to secure MongoDB with username and passwordHow do I drop a MongoDB database from the command line?MongoDB: update every document on one fieldMySQL vs MongoDB 1000 readsChecking if a field contains a string

UPDATE Person SET Name = FirstName + ' ' + LastName

db.person.update( ,  
 
 

UPDATE Person SET Name = FirstName + ' ' + LastName

db.person.update( ,  
 
 

UPDATE Person SET Name = FirstName + ' ' + LastName

db.person.update( , improve this answer

answered Jan 15 at 17:20

AldoAldo

42944 silver badges1111 bronze badges

add a comment )

share)

share)

share|improve this answer

answered Apr 3 '15 at 11:44

Chris GibbChris Gibb

52255 silver badges88 bronze badges

share|improve this answer

share|improve this answer

answered Apr 3 '15 at 11:44

Chris GibbChris Gibb

52255 silver badges88 bronze badges

answered Apr 3 '15 at 11:44

Chris GibbChris Gibb

52255 silver badges88 bronze badges

answered Apr 3 '15 at 11:44

Chris GibbChris Gibb

52255 silver badges88 bronze badges

52255 silver badges88 bronze badges

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  How is this different? Will the steam be throttled by the update activity? Do you have any reference to it? The Mongo docs are quite poor.
  
  – Nico
  Nov 21 '16 at 14:58
  

  
  
  
  

add a comment | 

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  How is this different? Will the steam be throttled by the update activity? Do you have any reference to it? The Mongo docs are quite poor.
  
  – Nico
  Nov 21 '16 at 14:58
  

  
  
  
  

1

1

How is this different? Will the steam be throttled by the update activity? Do you have any reference to it? The Mongo docs are quite poor.

– Nico
Nov 21 '16 at 14:58

How is this different? Will the steam be throttled by the update activity? Do you have any reference to it? The Mongo docs are quite poor.

– Nico
Nov 21 '16 at 14:58

add a comment | 

3

Regarding this answer, the snapshot function is deprecated in version 3.6, according to this update. So, on version 3.6 and above, it is possible to perform the operation this way:

db.person.find().forEach(
 function (elem) 
 db.person.update(
 
 _id: elem._id
 ,
 
 $set: 
 name: elem.firstname + ' ' + elem.lastname
 
 
 );
 
);

share|improve this answer

answered Jan 15 at 17:20

AldoAldo

42944 silver badges1111 bronze badges

add a comment | 

3

Regarding this answer, the snapshot function is deprecated in version 3.6, according to this update. So, on version 3.6 and above, it is possible to perform the operation this way:

db.person.find().forEach(
 function (elem) 
 db.person.update(
 
 _id: elem._id
 ,
 
 $set: 
 name: elem.firstname + ' ' + elem.lastname
 
 
 );
 
);

share|improve this answer

answered Jan 15 at 17:20

AldoAldo

42944 silver badges1111 bronze badges

add a comment | 

3

3

3

Regarding this answer, the snapshot function is deprecated in version 3.6, according to this update. So, on version 3.6 and above, it is possible to perform the operation this way:

db.person.find().forEach(
 function (elem) 
 db.person.update(
 
 _id: elem._id
 ,
 
 $set: 
 name: elem.firstname + ' ' + elem.lastname
 
 
 );
 
);

share|improve this answer

answered Jan 15 at 17:20

AldoAldo

42944 silver badges1111 bronze badges

Regarding this answer, the snapshot function is deprecated in version 3.6, according to this update. So, on version 3.6 and above, it is possible to perform the operation this way:

db.person.find().forEach(
 function (elem) 
 db.person.update(
 
 _id: elem._id
 ,
 
 $set: 
 name: elem.firstname + ' ' + elem.lastname
 
 
 );
 
);

share|improve this answer

answered Jan 15 at 17:20

AldoAldo

42944 silver badges1111 bronze badges

share|improve this answer

share|improve this answer

answered Jan 15 at 17:20

AldoAldo

42944 silver badges1111 bronze badges

answered Jan 15 at 17:20

AldoAldo

42944 silver badges1111 bronze badges

answered Jan 15 at 17:20

AldoAldo

42944 silver badges1111 bronze badges

42944 silver badges1111 bronze badges

add a comment | 

add a comment | 

2

Here's what we came up with for copying one field to another for ~150_000 records. It took about 6 minutes, but is still significantly less resource intensive than it would have been to instantiate and iterate over the same number of ruby objects.

js_query = %(
 $or : [
 
 'settings.mobile_notifications' : $exists : false ,
 'settings.mobile_admin_notifications' : $exists : false 
 
 ]
)

js_for_each = %(function(user) 
 if (!user.settings.hasOwnProperty('mobile_notifications')) 
 user.settings.mobile_notifications = user.settings.email_notifications;
 
 if (!user.settings.hasOwnProperty('mobile_admin_notifications')) 
 user.settings.mobile_admin_notifications = user.settings.email_admin_notifications;
 
 db.users.save(user);
)

js = "db.users.find(#js_query).forEach(#js_for_each);"
Mongoid::Sessions.default.command('$eval' => js)

share|improve this answer

answered Jun 8 '16 at 15:07

Chris BloomChris Bloom

2,53011 gold badge2727 silver badges4343 bronze badges

add a comment | 

2

Here's what we came up with for copying one field to another for ~150_000 records. It took about 6 minutes, but is still significantly less resource intensive than it would have been to instantiate and iterate over the same number of ruby objects.

js_query = %(
 $or : [
 
 'settings.mobile_notifications' : $exists : false ,
 'settings.mobile_admin_notifications' : $exists : false 
 
 ]
)

js_for_each = %(function(user) 
 if (!user.settings.hasOwnProperty('mobile_notifications')) 
 user.settings.mobile_notifications = user.settings.email_notifications;
 
 if (!user.settings.hasOwnProperty('mobile_admin_notifications')) 
 user.settings.mobile_admin_notifications = user.settings.email_admin_notifications;
 
 db.users.save(user);
)

js = "db.users.find(#js_query).forEach(#js_for_each);"
Mongoid::Sessions.default.command('$eval' => js)

share|improve this answer

answered Jun 8 '16 at 15:07

Chris BloomChris Bloom

2,53011 gold badge2727 silver badges4343 bronze badges

add a comment | 

2

2

2

Here's what we came up with for copying one field to another for ~150_000 records. It took about 6 minutes, but is still significantly less resource intensive than it would have been to instantiate and iterate over the same number of ruby objects.

js_query = %(
 $or : [
 
 'settings.mobile_notifications' : $exists : false ,
 'settings.mobile_admin_notifications' : $exists : false 
 
 ]
)

js_for_each = %(function(user) 
 if (!user.settings.hasOwnProperty('mobile_notifications')) 
 user.settings.mobile_notifications = user.settings.email_notifications;
 
 if (!user.settings.hasOwnProperty('mobile_admin_notifications')) 
 user.settings.mobile_admin_notifications = user.settings.email_admin_notifications;
 
 db.users.save(user);
)

js = "db.users.find(#js_query).forEach(#js_for_each);"
Mongoid::Sessions.default.command('$eval' => js)

share|improve this answer

answered Jun 8 '16 at 15:07

Chris BloomChris Bloom

2,53011 gold badge2727 silver badges4343 bronze badges

Here's what we came up with for copying one field to another for ~150_000 records. It took about 6 minutes, but is still significantly less resource intensive than it would have been to instantiate and iterate over the same number of ruby objects.

js_query = %(
 $or : [
 
 'settings.mobile_notifications' : $exists : false ,
 'settings.mobile_admin_notifications' : $exists : false 
 
 ]
)

js_for_each = %(function(user) 
 if (!user.settings.hasOwnProperty('mobile_notifications')) 
 user.settings.mobile_notifications = user.settings.email_notifications;
 
 if (!user.settings.hasOwnProperty('mobile_admin_notifications')) 
 user.settings.mobile_admin_notifications = user.settings.email_admin_notifications;
 
 db.users.save(user);
)

js = "db.users.find(#js_query).forEach(#js_for_each);"
Mongoid::Sessions.default.command('$eval' => js)

share|improve this answer

answered Jun 8 '16 at 15:07

Chris BloomChris Bloom

2,53011 gold badge2727 silver badges4343 bronze badges

share|improve this answer

share|improve this answer

answered Jun 8 '16 at 15:07

Chris BloomChris Bloom

2,53011 gold badge2727 silver badges4343 bronze badges

answered Jun 8 '16 at 15:07

Chris BloomChris Bloom

2,53011 gold badge2727 silver badges4343 bronze badges

answered Jun 8 '16 at 15:07

Chris BloomChris Bloom

2,53011 gold badge2727 silver badges4343 bronze badges

2,53011 gold badge2727 silver badges4343 bronze badges

add a comment | 

add a comment | 

0

Starting Mongo 4.2, db.collection.update() can accept an aggregation pipeline, finally allowing the update/creation of a field based on another field:

// firstName: "Hello", lastName: "World" 
db.collection.update(
 ,
 [ $set: name: $concat: [ "$firstName", " ", "$lastName" ] ],
 multi: true 
)
// "firstName" : "Hello", "lastName" : "World", "name" : "Hello World" 

• The first part is the match query, filtering which documents to update (in our case all documents).




• The second part [{ $set: name: ... ] is the update aggregation pipeline (note the squared brackets signifying the use of an aggregation pipeline). $set is a new aggregation operator and an alias of $addFields.




• Don't forget multi: true , otherwise only the first matching document will be updated.

share|improve this answer

edited Jun 11 at 23:03

answered Jun 11 at 20:35

Xavier GuihotXavier Guihot

10k1111 gold badges3333 silver badges3939 bronze badges

add a comment | 

0

Starting Mongo 4.2, db.collection.update() can accept an aggregation pipeline, finally allowing the update/creation of a field based on another field:

// firstName: "Hello", lastName: "World" 
db.collection.update(
 ,
 [ $set: name: $concat: [ "$firstName", " ", "$lastName" ] ],
 multi: true 
)
// "firstName" : "Hello", "lastName" : "World", "name" : "Hello World" 

• The first part is the match query, filtering which documents to update (in our case all documents).




• The second part [{ $set: name: ... ] is the update aggregation pipeline (note the squared brackets signifying the use of an aggregation pipeline). $set is a new aggregation operator and an alias of $addFields.




• Don't forget multi: true , otherwise only the first matching document will be updated.

share|improve this answer

edited Jun 11 at 23:03

answered Jun 11 at 20:35

Xavier GuihotXavier Guihot

10k1111 gold badges3333 silver badges3939 bronze badges

add a comment | 

0

0

0

Starting Mongo 4.2, db.collection.update() can accept an aggregation pipeline, finally allowing the update/creation of a field based on another field:

// firstName: "Hello", lastName: "World" 
db.collection.update(
 ,
 [ $set: name: $concat: [ "$firstName", " ", "$lastName" ] ],
 multi: true 
)
// "firstName" : "Hello", "lastName" : "World", "name" : "Hello World" 

• The first part is the match query, filtering which documents to update (in our case all documents).




• The second part [{ $set: name: ... ] is the update aggregation pipeline (note the squared brackets signifying the use of an aggregation pipeline). $set is a new aggregation operator and an alias of $addFields.




• Don't forget multi: true , otherwise only the first matching document will be updated.

share|improve this answer

edited Jun 11 at 23:03

answered Jun 11 at 20:35

Xavier GuihotXavier Guihot

10k1111 gold badges3333 silver badges3939 bronze badges

Starting Mongo 4.2, db.collection.update() can accept an aggregation pipeline, finally allowing the update/creation of a field based on another field:

// firstName: "Hello", lastName: "World" 
db.collection.update(
 ,
 [ $set: name: $concat: [ "$firstName", " ", "$lastName" ] ],
 multi: true 
)
// "firstName" : "Hello", "lastName" : "World", "name" : "Hello World" 

• The first part is the match query, filtering which documents to update (in our case all documents).




• The second part [{ $set: name: ... ] is the update aggregation pipeline (note the squared brackets signifying the use of an aggregation pipeline). $set is a new aggregation operator and an alias of $addFields.




• Don't forget multi: true , otherwise only the first matching document will be updated.

share|improve this answer

edited Jun 11 at 23:03

answered Jun 11 at 20:35

Xavier GuihotXavier Guihot

10k1111 gold badges3333 silver badges3939 bronze badges

share|improve this answer

share|improve this answer

edited Jun 11 at 23:03

edited Jun 11 at 23:03

edited Jun 11 at 23:03

answered Jun 11 at 20:35

Xavier GuihotXavier Guihot

10k1111 gold badges3333 silver badges3939 bronze badges

answered Jun 11 at 20:35

Xavier GuihotXavier Guihot

10k1111 gold badges3333 silver badges3939 bronze badges

answered Jun 11 at 20:35

Xavier GuihotXavier Guihot

10k1111 gold badges3333 silver badges3939 bronze badges

10k1111 gold badges3333 silver badges3939 bronze badges

add a comment | 

add a comment | 

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