Re^2: Using multiple values in a SQL "in" statement

in reply to Re: Using multiple values in a SQL "in" statement
in thread Using multiple values in a SQL "in" statement

This worked great. thanks. Can you give me a brief explanation of what's happening at this line? my $question_mark_string = join(',', ('?') x scalar(@id) );

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Re^3: Using multiple values in a SQL "in" statement by jhourcle (Prior) on May 05, 2013 at 13:07 UTC
It's three operations. The `x` operator, is either a string or list multiplier. Here, it's being used on an list, as the item is in parens: `('?') x scalar(@id)` `scalar(@id)` gives the number of items in the array. So we end up with a list of question marks the same size as the `@id` array. The `join` will flatten a list into a single string, placing the first argument in between each item. So we're placing a comma between each of the question marks.	[reply] [d/l] [select]

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Re^3: Using multiple values in a SQL "in" statement
by jhourcle (Prior) on May 05, 2013 at 13:07 UTC

It's three operations. The x operator, is either a string or list multiplier. Here, it's being used on an list, as the item is in parens:

('?') x scalar(@id)

scalar(@id) gives the number of items in the array. So we end up with a list of question marks the same size as the @id array.

The join will flatten a list into a single string, placing the first argument in between each item. So we're placing a comma between each of the question marks.

[reply]
[d/l]
[select]

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