问题
SQL Server has Table Value Parameters which allows you to pass an array of values as a parameter.
What is the appropiate way to achieve something similar to a PostgreSQL query so I can do something like:
select * from product where id in ($1)
I'm using Npgsql .NET library.
https://www.nuget.org/packages/Npgsql/3.0.5
回答1:
In PostgreSQL you can use arrays instead of list of IDs like:
... where id = any('{1, 2, 3}'::int[])
or
... where id = any(array[1, 2, 3])
which means that id is one of the array's items.
Read more about arrays operators and functions.
To pass array as a parameter from third party languages you can use at least first variant:
... where id = any($1 ::int[])
where $1 is a string parameter looks like {1, 2, 3}. Note that a space between $1 and ::int[] - it may be necessary for some clients.
Not sure about C# is it supports array parameters directly.
回答2:
In Postgres you can use IN operator in two ways:
expression IN (value [, ...])
expression IN (subquery)
Read in the documetation: first variant, second variant or this overview.
来源：https://stackoverflow.com/questions/35273060/postgresql-equivalent-to-sql-servers-tvp