python - Getting random row through SQLAlchemy -

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how select a(or some) random row(s) table using sqlalchemy?

this database-specific issue.

i know postgresql , mysql have ability order random function, can use in sqlalchemy:

from  sqlalchemy.sql.expression import func, select  select.order_by(func.random()) # postgresql, sqlite  select.order_by(func.rand()) # mysql  select.order_by('dbms_random.value') # oracle

next, need limit query number of records need (for example using .limit()).

bear in mind @ least in postgresql, selecting random record has severe perfomance issues; here article it.


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