python - Fastest way to fetch value of just one field of an instance in Django -

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let's have model this:

class a(models.model):     title = models.charfield(max_length=10)     (more fields)

i want fetch value of title field of instance. can either use filter:

a.objects.filter(id=1).values_list('title', flat=true)

which generates sql statement this:

select "app_table_a"."title" "app_table_a" ("app_table_a"."a_id" = 1) limit whatever

or use get:

a.objects.get(id=1).title

which generates this:

select "app_table_a"."id", "app_table_a"."title", ... ,"app_table_a"."all fields in model" "app_table_a" ("app_table_a"."a_id" = 1)

the difference in select part of queries, gives impression first approach better option. when @ execution time of statements, don't see meaningful difference , both statements fluctuate around, example, 25ms.

so, question whether there difference, performance-wise (specially huge databases , models many fields), or twisting long statements?

yes, agree you.there no significant difference in between them(in perfomance when 1 record) because, behind scenes django get() method runs filter() method, checks filter results set 1 record.


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