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Query an array of hashes (Rails 5.2)

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2

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street , model: :Address, field_type: :string ,
 name: :city , model: :Address, field_type: :string ,
 name: :count , model: :Property, field_type: :integer , 
 name: :count2 , model: :Property, field_type: :integer ,
 name: :count3 , model: :Property, field_type: :integer ,
 name: :count3 , model: :Property, field_type: :integer 
 ]

I have an array of hashes and I would like to query the hash values. I would like to know the most efficient and most recommended solution.

For example, I may need to find all the names of the hashes that are :integer. OR I may want to query all the names of the models that are :Address. OR I may need to query all the field_types as unique.

Can I query the array of hashes directly? if so how, and if not, is there a better method using active model or something?

ruby-on-rails ruby ruby-on-rails-5.2

share|improve this question

edited Mar 8 at 1:59

user2012677

asked Mar 8 at 1:50

user2012677user2012677

1,52141640

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  If it's a hash of hashes, then it's missing a few values or keys. For example: data = 1: name: :name, model: :Address, field_type: :string
  
  – pauloancheta
  Mar 8 at 1:58
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  sorry, I mean array of hashes, fixed
  
  – user2012677
  Mar 8 at 1:59
  
  

  
  
  
  

add a comment | 

2

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street , model: :Address, field_type: :string ,
 name: :city , model: :Address, field_type: :string ,
 name: :count , model: :Property, field_type: :integer , 
 name: :count2 , model: :Property, field_type: :integer ,
 name: :count3 , model: :Property, field_type: :integer ,
 name: :count3 , model: :Property, field_type: :integer 
 ]

I have an array of hashes and I would like to query the hash values. I would like to know the most efficient and most recommended solution.

For example, I may need to find all the names of the hashes that are :integer. OR I may want to query all the names of the models that are :Address. OR I may need to query all the field_types as unique.

Can I query the array of hashes directly? if so how, and if not, is there a better method using active model or something?

ruby-on-rails ruby ruby-on-rails-5.2

share|improve this question

edited Mar 8 at 1:59

user2012677

asked Mar 8 at 1:50

user2012677user2012677

1,52141640

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  If it's a hash of hashes, then it's missing a few values or keys. For example: data = 1: name: :name, model: :Address, field_type: :string
  
  – pauloancheta
  Mar 8 at 1:58
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  sorry, I mean array of hashes, fixed
  
  – user2012677
  Mar 8 at 1:59
  
  

  
  
  
  

add a comment | 

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street , model: :Address, field_type: :string ,
 name: :city , model: :Address, field_type: :string ,
 name: :count , model: :Property, field_type: :integer , 
 name: :count2 , model: :Property, field_type: :integer ,
 name: :count3 , model: :Property, field_type: :integer ,
 name: :count3 , model: :Property, field_type: :integer 
 ]

I have an array of hashes and I would like to query the hash values. I would like to know the most efficient and most recommended solution.

For example, I may need to find all the names of the hashes that are :integer. OR I may want to query all the names of the models that are :Address. OR I may need to query all the field_types as unique.

Can I query the array of hashes directly? if so how, and if not, is there a better method using active model or something?

ruby-on-rails ruby ruby-on-rails-5.2

share|improve this question

edited Mar 8 at 1:59

user2012677

asked Mar 8 at 1:50

user2012677user2012677

1,52141640

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street , model: :Address, field_type: :string ,
 name: :city , model: :Address, field_type: :string ,
 name: :count , model: :Property, field_type: :integer , 
 name: :count2 , model: :Property, field_type: :integer ,
 name: :count3 , model: :Property, field_type: :integer ,
 name: :count3 , model: :Property, field_type: :integer 
 ]

share|improve this question

edited Mar 8 at 1:59

user2012677

asked Mar 8 at 1:50

user2012677user2012677

1,52141640

share|improve this question

edited Mar 8 at 1:59

user2012677

asked Mar 8 at 1:50

user2012677user2012677

1,52141640

asked Mar 8 at 1:50

user2012677user2012677

1,52141640

asked Mar 8 at 1:50

user2012677user2012677

1,52141640

1 Answer
1

active

oldest

votes

3

You have a "plain" array of hashes. You can use Ruby methods:

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street, model: :Address, field_type: :string ,
 name: :city, model: :Address, field_type: :string ,
 name: :count, model: :Property, field_type: :integer , 
 name: :count2, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer 
]

p data.select val[:field_type] == :integer .map val
# [:count, :count2, :count3, :count3]
p data.select .map val
# [:name, :country, :street, :city]
p data.uniq val[:field_type] 
# [:name=>:name, :model=>:Address, :field_type=>:string, :name=>:count, :model=>:Property, :field_type=>:integer]

share|improve this answer

answered Mar 8 at 2:01

Sebastian PalmaSebastian Palma

16.1k42135

add a comment | 

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3

You have a "plain" array of hashes. You can use Ruby methods:

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street, model: :Address, field_type: :string ,
 name: :city, model: :Address, field_type: :string ,
 name: :count, model: :Property, field_type: :integer , 
 name: :count2, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer 
]

p data.select val[:field_type] == :integer .map val
# [:count, :count2, :count3, :count3]
p data.select .map val
# [:name, :country, :street, :city]
p data.uniq val[:field_type] 
# [:name=>:name, :model=>:Address, :field_type=>:string, :name=>:count, :model=>:Property, :field_type=>:integer]

share|improve this answer

answered Mar 8 at 2:01

Sebastian PalmaSebastian Palma

16.1k42135

add a comment | 

3

You have a "plain" array of hashes. You can use Ruby methods:

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street, model: :Address, field_type: :string ,
 name: :city, model: :Address, field_type: :string ,
 name: :count, model: :Property, field_type: :integer , 
 name: :count2, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer 
]

p data.select val[:field_type] == :integer .map val
# [:count, :count2, :count3, :count3]
p data.select .map val
# [:name, :country, :street, :city]
p data.uniq val[:field_type] 
# [:name=>:name, :model=>:Address, :field_type=>:string, :name=>:count, :model=>:Property, :field_type=>:integer]

share|improve this answer

answered Mar 8 at 2:01

Sebastian PalmaSebastian Palma

16.1k42135

add a comment | 

You have a "plain" array of hashes. You can use Ruby methods:

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street, model: :Address, field_type: :string ,
 name: :city, model: :Address, field_type: :string ,
 name: :count, model: :Property, field_type: :integer , 
 name: :count2, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer 
]

p data.select val[:field_type] == :integer .map val
# [:count, :count2, :count3, :count3]
p data.select .map val
# [:name, :country, :street, :city]
p data.uniq val[:field_type] 
# [:name=>:name, :model=>:Address, :field_type=>:string, :name=>:count, :model=>:Property, :field_type=>:integer]

share|improve this answer

answered Mar 8 at 2:01

Sebastian PalmaSebastian Palma

16.1k42135

data = [
 name: :name, model: :Address, field_type: :string ,
 name: :country, model: :Address, field_type: :string ,
 name: :street, model: :Address, field_type: :string ,
 name: :city, model: :Address, field_type: :string ,
 name: :count, model: :Property, field_type: :integer , 
 name: :count2, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer ,
 name: :count3, model: :Property, field_type: :integer 
]

p data.select val[:field_type] == :integer .map val
# [:count, :count2, :count3, :count3]
p data.select .map val
# [:name, :country, :street, :city]
p data.uniq val[:field_type] 
# [:name=>:name, :model=>:Address, :field_type=>:string, :name=>:count, :model=>:Property, :field_type=>:integer]

share|improve this answer

answered Mar 8 at 2:01

Sebastian PalmaSebastian Palma

16.1k42135

answered Mar 8 at 2:01

Sebastian PalmaSebastian Palma

16.1k42135

answered Mar 8 at 2:01

Sebastian PalmaSebastian Palma

16.1k42135