Sum in each loop when object might be nil

I'm trying to loop though a set of objects (people) and sum the values of a bunch of objects that belongs_to :person, for example to get the cumulative years of different types of experience of a group of people

@people.each do |person|



  finance_experience_sum += person.finance_experience.value

  management_experience_sum += person.manangement_experience.value

  clerical_experience_sum += person.clerical_experience.value



end

However, sometimes I get this error when a person doesn't have a certain type of experience. What's the easiest way to fix this in my each loop?

undefined method `value' for nil:NilClass

I understand why I'm getting the error, but not sure what is the easiest way to get past it in this scenario

edited Jan 1 at 9:46

iGian

4,4692625

asked Jan 1 at 2:11

phauwn

87111

1

@phauwni have replied to your question please check.

– Cryptex Technologies
Jan 1 at 5:25

Can you share your models and relations? I'm missing something.

– iGian
Jan 1 at 9:57

add a comment |

@people.each do |person|



  finance_experience_sum += person.finance_experience.value

  management_experience_sum += person.manangement_experience.value

  clerical_experience_sum += person.clerical_experience.value



end

However, sometimes I get this error when a person doesn't have a certain type of experience. What's the easiest way to fix this in my each loop?

undefined method `value' for nil:NilClass

I understand why I'm getting the error, but not sure what is the easiest way to get past it in this scenario

edited Jan 1 at 9:46

iGian

4,4692625

asked Jan 1 at 2:11

phauwn

87111

1

@phauwni have replied to your question please check.

– Cryptex Technologies
Jan 1 at 5:25

Can you share your models and relations? I'm missing something.

– iGian
Jan 1 at 9:57

add a comment |

@people.each do |person|



  finance_experience_sum += person.finance_experience.value

  management_experience_sum += person.manangement_experience.value

  clerical_experience_sum += person.clerical_experience.value



end

However, sometimes I get this error when a person doesn't have a certain type of experience. What's the easiest way to fix this in my each loop?

undefined method `value' for nil:NilClass

I understand why I'm getting the error, but not sure what is the easiest way to get past it in this scenario

edited Jan 1 at 9:46

iGian

4,4692625

asked Jan 1 at 2:11

phauwn

87111

@people.each do |person|



  finance_experience_sum += person.finance_experience.value

  management_experience_sum += person.manangement_experience.value

  clerical_experience_sum += person.clerical_experience.value



end

However, sometimes I get this error when a person doesn't have a certain type of experience. What's the easiest way to fix this in my each loop?

undefined method `value' for nil:NilClass

I understand why I'm getting the error, but not sure what is the easiest way to get past it in this scenario

ruby-on-rails

edited Jan 1 at 9:46

iGian

4,4692625

asked Jan 1 at 2:11

phauwn

87111

edited Jan 1 at 9:46

iGian

4,4692625

asked Jan 1 at 2:11

phauwn

87111

edited Jan 1 at 9:46

iGian

4,4692625

edited Jan 1 at 9:46

iGian

4,4692625

edited Jan 1 at 9:46

iGian

4,4692625

asked Jan 1 at 2:11

phauwn

87111

asked Jan 1 at 2:11

phauwn

87111

asked Jan 1 at 2:11

phauwn

87111

1

@phauwni have replied to your question please check.

– Cryptex Technologies
Jan 1 at 5:25

Can you share your models and relations? I'm missing something.

– iGian
Jan 1 at 9:57

add a comment |

1

@phauwni have replied to your question please check.

– Cryptex Technologies
Jan 1 at 5:25

Can you share your models and relations? I'm missing something.

– iGian
Jan 1 at 9:57

@phauwni have replied to your question please check.

– Cryptex Technologies
Jan 1 at 5:25

Can you share your models and relations? I'm missing something.

– iGian
Jan 1 at 9:57

add a comment |

2 Answers
2

active

oldest

votes

You can do simply like these without using the each loop

finance_experience_sum = People.includes(:finance_experience).sum(:value)

management_experience_sum = People.includes(:manangement_experience).sum(:value)

clerical_experience_sum = People.includes(:clerical_experience).sum(:value)

Always used ruby on rails best practices and predefined methods of ruby.

answered Jan 1 at 5:24

Cryptex Technologies

800213

1

upvoted for reliable answer but need @people in place of People

– ray
Jan 2 at 11:07

need change in your profile link(experience section) for ajaydhande.github.io for carrier (need to be career)

– ray
Jan 2 at 11:09

Okay thanks for your suggestions

– Cryptex Technologies
Jan 2 at 11:11

@ray i will do that

– Cryptex Technologies
Jan 2 at 11:11

Perfect, thank you. This is the best practice lesson I needed.

– phauwn
Jan 2 at 21:43

add a comment |

You should follow best practices like include nested records using includes that will avoid N+1 query problem.

If you want to do it anyway then try following:

  finance_experience_sum    += person.try(:finance_experience).try(:value).to_i #or to_f if float value

  management_experience_sum += person.try(:manangement_experience).try(:value).to_i

  clerical_experience_sum   += person.try(:clerical_experience).try(:value).to_i

If you are using ruby 2.4 or later then use:

  finance_experience_sum    += person&.finance_experience&.value&.to_i

  management_experience_sum += person&.manangement_experience&.value&.to_i

  clerical_experience_sum   += person&.clerical_experience&.value&.to_i

answered Jan 1 at 10:11

G.B

2,90821539

add a comment |

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2 Answers
2

active

oldest

votes

2 Answers
2

active

oldest

votes

You can do simply like these without using the each loop

finance_experience_sum = People.includes(:finance_experience).sum(:value)

management_experience_sum = People.includes(:manangement_experience).sum(:value)

clerical_experience_sum = People.includes(:clerical_experience).sum(:value)

Always used ruby on rails best practices and predefined methods of ruby.

answered Jan 1 at 5:24

Cryptex Technologies

800213

1

upvoted for reliable answer but need @people in place of People

– ray
Jan 2 at 11:07

need change in your profile link(experience section) for ajaydhande.github.io for carrier (need to be career)

– ray
Jan 2 at 11:09

Okay thanks for your suggestions

– Cryptex Technologies
Jan 2 at 11:11

@ray i will do that

– Cryptex Technologies
Jan 2 at 11:11

Perfect, thank you. This is the best practice lesson I needed.

– phauwn
Jan 2 at 21:43

add a comment |

You can do simply like these without using the each loop

finance_experience_sum = People.includes(:finance_experience).sum(:value)

management_experience_sum = People.includes(:manangement_experience).sum(:value)

clerical_experience_sum = People.includes(:clerical_experience).sum(:value)

Always used ruby on rails best practices and predefined methods of ruby.

answered Jan 1 at 5:24

Cryptex Technologies

800213

1

upvoted for reliable answer but need @people in place of People

– ray
Jan 2 at 11:07

need change in your profile link(experience section) for ajaydhande.github.io for carrier (need to be career)

– ray
Jan 2 at 11:09

Okay thanks for your suggestions

– Cryptex Technologies
Jan 2 at 11:11

@ray i will do that

– Cryptex Technologies
Jan 2 at 11:11

Perfect, thank you. This is the best practice lesson I needed.

– phauwn
Jan 2 at 21:43

add a comment |

You can do simply like these without using the each loop

finance_experience_sum = People.includes(:finance_experience).sum(:value)

management_experience_sum = People.includes(:manangement_experience).sum(:value)

clerical_experience_sum = People.includes(:clerical_experience).sum(:value)

Always used ruby on rails best practices and predefined methods of ruby.

answered Jan 1 at 5:24

Cryptex Technologies

800213

You can do simply like these without using the each loop

finance_experience_sum = People.includes(:finance_experience).sum(:value)

management_experience_sum = People.includes(:manangement_experience).sum(:value)

clerical_experience_sum = People.includes(:clerical_experience).sum(:value)

Always used ruby on rails best practices and predefined methods of ruby.

answered Jan 1 at 5:24

Cryptex Technologies

800213

answered Jan 1 at 5:24

Cryptex Technologies

800213

answered Jan 1 at 5:24

Cryptex Technologies

800213

answered Jan 1 at 5:24

Cryptex Technologies

800213

1

upvoted for reliable answer but need @people in place of People

– ray
Jan 2 at 11:07

need change in your profile link(experience section) for ajaydhande.github.io for carrier (need to be career)

– ray
Jan 2 at 11:09

Okay thanks for your suggestions

– Cryptex Technologies
Jan 2 at 11:11

@ray i will do that

– Cryptex Technologies
Jan 2 at 11:11

Perfect, thank you. This is the best practice lesson I needed.

– phauwn
Jan 2 at 21:43

add a comment |

1

upvoted for reliable answer but need @people in place of People

– ray
Jan 2 at 11:07

need change in your profile link(experience section) for ajaydhande.github.io for carrier (need to be career)

– ray
Jan 2 at 11:09

Okay thanks for your suggestions

– Cryptex Technologies
Jan 2 at 11:11

@ray i will do that

– Cryptex Technologies
Jan 2 at 11:11

Perfect, thank you. This is the best practice lesson I needed.

– phauwn
Jan 2 at 21:43

upvoted for reliable answer but need @people in place of People

– ray
Jan 2 at 11:07

need change in your profile link(experience section) for ajaydhande.github.io for carrier (need to be career)

– ray
Jan 2 at 11:09

Okay thanks for your suggestions

– Cryptex Technologies
Jan 2 at 11:11

@ray i will do that

– Cryptex Technologies
Jan 2 at 11:11

Perfect, thank you. This is the best practice lesson I needed.

– phauwn
Jan 2 at 21:43

add a comment |

You should follow best practices like include nested records using includes that will avoid N+1 query problem.

If you want to do it anyway then try following:

  finance_experience_sum    += person.try(:finance_experience).try(:value).to_i #or to_f if float value

  management_experience_sum += person.try(:manangement_experience).try(:value).to_i

  clerical_experience_sum   += person.try(:clerical_experience).try(:value).to_i

If you are using ruby 2.4 or later then use:

  finance_experience_sum    += person&.finance_experience&.value&.to_i

  management_experience_sum += person&.manangement_experience&.value&.to_i

  clerical_experience_sum   += person&.clerical_experience&.value&.to_i

answered Jan 1 at 10:11

G.B

2,90821539

add a comment |

You should follow best practices like include nested records using includes that will avoid N+1 query problem.

If you want to do it anyway then try following:

  finance_experience_sum    += person.try(:finance_experience).try(:value).to_i #or to_f if float value

  management_experience_sum += person.try(:manangement_experience).try(:value).to_i

  clerical_experience_sum   += person.try(:clerical_experience).try(:value).to_i

If you are using ruby 2.4 or later then use:

  finance_experience_sum    += person&.finance_experience&.value&.to_i

  management_experience_sum += person&.manangement_experience&.value&.to_i

  clerical_experience_sum   += person&.clerical_experience&.value&.to_i

answered Jan 1 at 10:11

G.B

2,90821539

add a comment |

You should follow best practices like include nested records using includes that will avoid N+1 query problem.

If you want to do it anyway then try following:

  finance_experience_sum    += person.try(:finance_experience).try(:value).to_i #or to_f if float value

  management_experience_sum += person.try(:manangement_experience).try(:value).to_i

  clerical_experience_sum   += person.try(:clerical_experience).try(:value).to_i

If you are using ruby 2.4 or later then use:

  finance_experience_sum    += person&.finance_experience&.value&.to_i

  management_experience_sum += person&.manangement_experience&.value&.to_i

  clerical_experience_sum   += person&.clerical_experience&.value&.to_i

answered Jan 1 at 10:11

G.B

2,90821539

You should follow best practices like include nested records using includes that will avoid N+1 query problem.

If you want to do it anyway then try following:

  finance_experience_sum    += person.try(:finance_experience).try(:value).to_i #or to_f if float value

  management_experience_sum += person.try(:manangement_experience).try(:value).to_i

  clerical_experience_sum   += person.try(:clerical_experience).try(:value).to_i

If you are using ruby 2.4 or later then use:

  finance_experience_sum    += person&.finance_experience&.value&.to_i

  management_experience_sum += person&.manangement_experience&.value&.to_i

  clerical_experience_sum   += person&.clerical_experience&.value&.to_i

answered Jan 1 at 10:11

G.B

2,90821539

answered Jan 1 at 10:11

G.B

2,90821539

answered Jan 1 at 10:11

G.B

2,90821539

answered Jan 1 at 10:11

G.B

2,90821539

add a comment |

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