Mixing
using has_many: primary_key when it isn't the primary_key in the database
I'm working on a codebase that uses rails and the previous developers have created a few models in postgres that are references to each other. However they use activerecord's primary_key field even though the database doesn't show that field as the primary_key. Is there any benefit or disadvantage to this? Keep in mind there is an index on the 'fake' primary_key field .
# models
class A < ActiveRecord:Base
has_many :bs, primary_key: :special_id
end
class B < ActiveRecord::Base
belongs_to :a, primary_key: :special_id, foreign_key: :special_id
end
Actual primary_key is id on B but schema includes id and special_id. Index exists on special_id
ruby-on-rails postgresql activerecord
asked Jan 2 at 16:34
Terence ChowTerence Chow
3,935154794
add a comment |
I'm working on a codebase that uses rails and the previous developers have created a few models in postgres that are references to each other. However they use activerecord's primary_key field even though the database doesn't show that field as the primary_key. Is there any benefit or disadvantage to this? Keep in mind there is an index on the 'fake' primary_key field .
# models
class A < ActiveRecord:Base
has_many :bs, primary_key: :special_id
end
class B < ActiveRecord::Base
belongs_to :a, primary_key: :special_id, foreign_key: :special_id
end
Actual primary_key is id on B but schema includes id and special_id. Index exists on special_id
ruby-on-rails postgresql activerecord
asked Jan 2 at 16:34
Terence ChowTerence Chow
3,935154794
add a comment |
I'm working on a codebase that uses rails and the previous developers have created a few models in postgres that are references to each other. However they use activerecord's primary_key field even though the database doesn't show that field as the primary_key. Is there any benefit or disadvantage to this? Keep in mind there is an index on the 'fake' primary_key field .
# models
class A < ActiveRecord:Base
has_many :bs, primary_key: :special_id
end
class B < ActiveRecord::Base
belongs_to :a, primary_key: :special_id, foreign_key: :special_id
end
Actual primary_key is id on B but schema includes id and special_id. Index exists on special_id
ruby-on-rails postgresql activerecord
asked Jan 2 at 16:34
Terence ChowTerence Chow
3,935154794
I'm working on a codebase that uses rails and the previous developers have created a few models in postgres that are references to each other. However they use activerecord's primary_key field even though the database doesn't show that field as the primary_key. Is there any benefit or disadvantage to this? Keep in mind there is an index on the 'fake' primary_key field .
# models
class A < ActiveRecord:Base
has_many :bs, primary_key: :special_id
end
class B < ActiveRecord::Base
belongs_to :a, primary_key: :special_id, foreign_key: :special_id
end
Actual primary_key is id on B but schema includes id and special_id. Index exists on special_id
ruby-on-rails postgresql activerecord
ruby-on-rails postgresql activerecord
asked Jan 2 at 16:34
Terence ChowTerence Chow
3,935154794
asked Jan 2 at 16:34
Terence ChowTerence Chow
3,935154794
asked Jan 2 at 16:34
Terence ChowTerence Chow
3,935154794
asked Jan 2 at 16:34
Terence ChowTerence Chow
3,935154794
asked Jan 2 at 16:34
Terence ChowTerence Chow
3,935154794
3,935154794
add a comment |
add a comment |
1 Answer
1
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oldest
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The benefit, in theory, is that it's more readable. In your case A.find(id).bs would join the Bs that have a corresponding b_id in your A table, which may not be as intuitive as using another name, in this case special_id.
From a performance standpoint it should make no noticeable difference, provided there are indexes on both the primary and foreign key columns. The has_many method will ultimately result in a query, so the only computational cost is to swap out the column name in the query string that ActiveRecord generates.
You could try benchmarking the queries with the various key declarations, but I'd be amazed if it added even a millisecond to the query time.
answered Jan 2 at 17:54
NM PennypackerNM Pennypacker
4,692112531
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
The benefit, in theory, is that it's more readable. In your case A.find(id).bs would join the Bs that have a corresponding b_id in your A table, which may not be as intuitive as using another name, in this case special_id.
From a performance standpoint it should make no noticeable difference, provided there are indexes on both the primary and foreign key columns. The has_many method will ultimately result in a query, so the only computational cost is to swap out the column name in the query string that ActiveRecord generates.
You could try benchmarking the queries with the various key declarations, but I'd be amazed if it added even a millisecond to the query time.
answered Jan 2 at 17:54
NM PennypackerNM Pennypacker
4,692112531
add a comment |
The benefit, in theory, is that it's more readable. In your case A.find(id).bs would join the Bs that have a corresponding b_id in your A table, which may not be as intuitive as using another name, in this case special_id.
From a performance standpoint it should make no noticeable difference, provided there are indexes on both the primary and foreign key columns. The has_many method will ultimately result in a query, so the only computational cost is to swap out the column name in the query string that ActiveRecord generates.
You could try benchmarking the queries with the various key declarations, but I'd be amazed if it added even a millisecond to the query time.
answered Jan 2 at 17:54
NM PennypackerNM Pennypacker
4,692112531
add a comment |
The benefit, in theory, is that it's more readable. In your case A.find(id).bs would join the Bs that have a corresponding b_id in your A table, which may not be as intuitive as using another name, in this case special_id.
From a performance standpoint it should make no noticeable difference, provided there are indexes on both the primary and foreign key columns. The has_many method will ultimately result in a query, so the only computational cost is to swap out the column name in the query string that ActiveRecord generates.
You could try benchmarking the queries with the various key declarations, but I'd be amazed if it added even a millisecond to the query time.
answered Jan 2 at 17:54
NM PennypackerNM Pennypacker
4,692112531
The benefit, in theory, is that it's more readable. In your case A.find(id).bs would join the Bs that have a corresponding b_id in your A table, which may not be as intuitive as using another name, in this case special_id.
From a performance standpoint it should make no noticeable difference, provided there are indexes on both the primary and foreign key columns. The has_many method will ultimately result in a query, so the only computational cost is to swap out the column name in the query string that ActiveRecord generates.
You could try benchmarking the queries with the various key declarations, but I'd be amazed if it added even a millisecond to the query time.
answered Jan 2 at 17:54
NM PennypackerNM Pennypacker
4,692112531
answered Jan 2 at 17:54
NM PennypackerNM Pennypacker
4,692112531
answered Jan 2 at 17:54
NM PennypackerNM Pennypacker
4,692112531
answered Jan 2 at 17:54
NM PennypackerNM Pennypacker
4,692112531
4,692112531
add a comment |
add a comment |
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