Such a variable parameter is, in SQL-context, normally called a 'placeholder', and denoted by '?'.

DBD::SQLite manual on Placeholders

UPDATE: After more careful reading I realize you are looking for the SQL IN construct: select  .... where value1 in ('apple', 'pie') In this case I don't think you can use a placeholder to represent the possibly multiple values inside the IN(), i.e., you need separate sql statements for separate numbers of ? as IN() parameters.

As DBI docs say: "placeholders can only represent single scalar values".

(In PostgreSQL this problem can be avoided by (standard SQL): WHERE value1 = ANY ( ? ) or (postgres-specific SQL): WHERE array[value1] <@ ( ? ) which you can then execute, passing in an arrayref for the (single!) placeholder. Both forms are indexable and fast (in a quick 1GB test table with a rowcount of 10M (retrieving 20 rows) takes less than 1 ms). SQLite does not know how to do this (I actually tried but alas ...)) so you are reduced to constructing SQL-statements dependent on the size of the search-set (see other replies). )

In reply to Re: dbi:SQLite multiple query by erix
in thread dbi:SQLite multiple query by Anonymous Monk

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