NAME

SQL::Bind - SQL flexible placeholders

SYNOPSIS

use SQL::Bind qw(sql);
# Scalars
my ($sql, @bind) =
  sql 'SELECT foo FROM bar WHERE id=:id AND status=:status',
  id     => 1,
  status => 'active';
# Arrays
my ($sql, @bind) = sql 'SELECT foo FROM bar WHERE id IN (:id)', id => [1, 2, 3];
# Hashes
my ($sql, @bind) = sql 'UPDATE bar SET :columns', columns => {foo => 'bar'};
# Raw values (!)
my ($sql, @bind) = sql 'INSERT INTO bar (:keys!) VALUES (:values)',
  keys   => [qw/foo/],
  values => [qw/bar/];
# Recursive binding (*)
my ($sql, @bind) =
  sql 'SELECT foo FROM bar WHERE :recursive_query*',
  recursive_query => 'name = :name',
  name            => 'hello';

DESCRIPTION

SQL::Bind simplifies SQL queries maintenance by introducing placeholders. The behavior of the replacement depends on
the type of the value. Scalars, Arrays and Hashes are supported.

Configuration

$PlaceholderPrefix

Placeholder prefix (: by default) can be changed by setting the $PlaceholderPrefix global variable:

local $SQL::Bind::PlaceholderPrefix = '@';
my ($sql, @bind) =
  sql 'SELECT foo FROM bar WHERE id=@id',
  id => 1;

Placeholders

A placeholders is an alphanumeric sequence that is prefixed with : (by default) and can end with ! for raw values
or * for recursive binding. Some examples:

:name
:status
:CamelCase
:Value_123
:ThisWillBeInsertedAsIs!
:recursive*

Scalar values

Every value is replaced with a ?.

my ($sql, @bind) =
  sql 'SELECT foo FROM bar WHERE id=:id AND status=:status',
  id     => 1,
  status => 'active';
# SELECT foo FROM bar WHERE id=? AND status=?
# [1, 'active']

Array values

Arrays are replaced with a sequence of ?, ?, ....

my ($sql, @bind) = sql 'SELECT foo FROM bar WHERE id IN (:id)', id => [1, 2, 3];
# SELECT foo FROM bar WHERE id IN (?, ?, ?)
# [1, 2, 3]

Hash values

Hahes are replaced with a sequence of key1=?, key2=?, ....

my ($sql, @bind) = sql 'UPDATE bar SET :columns', columns => {foo => 'bar'};
# UPDATE bar SET foo=?
# ['bar']

Raw values

Sometimes raw values are needed be it another identifier, or a list of columns (e.g. INSERT, UPDATE). For this case
a placeholder should be suffixed with a !.

my ($sql, @bind) = sql 'INSERT INTO bar (:keys!) VALUES (:values)',
  keys   => [qw/foo/],
  values => [qw/bar/];
# INSERT INTO bar (foo) VALUES (?)
# ['bar']

Recursive binding

Recursive binding allows you to recursively parse already replaced values. This helps building complex subqueries.

my ($sql, @bind) =
  sql 'SELECT foo FROM bar WHERE :recursive_query*',
  recursive_query => 'name = :name',
  name            => 'hello';
# 'SELECT foo FROM bar WHERE name = ?
# ['hello']

DEVELOPMENT

Repository

http://github.com/vti/sql-bind

CREDITS

AUTHOR

Viacheslav Tykhanovskyi, vti@cpan.org.

COPYRIGHT AND LICENSE

Copyright (C) 2020, Viacheslav Tykhanovskyi

This program is free software, you can redistribute it and/or modify it under
the terms of the Artistic License version 2.0.