NAME
EntityModel::Query - handle SQL queries
VERSION
version 0.003
SYNOPSIS
use EntityModel::Query;
my $query = EntityModel::Query->new(
select => [qw(id name)]
from => 'table',
where => [ created => { '<' => '2010-01-01' } ],
limit => 5
);
my ($sql, @bind) = $query->sqlAndParameters;
my $sth = $dbh->prepare($sql);
$sth->execute(@bind);DESCRIPTION
Provides an abstraction layer for building SQL queries programmatically.
When generating the query, each of the components is called in turn to get an "inline SQL" arrayref. This is an arrayref consisting of SQL string fragments interspersed with refs for items such as EntityModel::Entity names, direct scalar values, or EntityModel::Field names.
As an example:
[ 'select * from ', EntityModel::Entity->new('table'), ' where ', EntityModel::Field->new('something'), ' = ', \3 ]This can then be used by sqlAndParameters to generate:
'select * from "table" where "something" = ?', 3or as a plain SQL string (perhaps for diagnostic purposes) from sqlString as:
'select * from "table" where "something" = 3'METHODS
new
Construct a new EntityModel::Query. Most of the work is passed off to parseSpec.
type
Returns the type of the current query. The query object will be reblessed into an appropriate subclass depending on whether this is an insert, select, delete etc. A query that has not been reblessed is invalid.
parseSpec
Parse the specification we were given.
parse_base
Base method for parsing.
reclassify
Virtual method to allow subclass to perform any required updates after reblessing to an alternative class.
upgradeTo
Upgrade an existing EntityModel::Query object to a subclass.
parse_limit
Handle a 'limit' directive.
parse_group
parse_where
typeSQL
Proxy method for type, returns the SQL string representation for the current query type (such as 'select' or 'insert into').
fieldsSQL
Generate the SQL for fields.
fromSQL
SQL for the 'from' clause.
limitSQL
offsetSQL
orderSQL
groupSQL
havingSQL
whereSQL
joinSQL
keyword_order { qw{type fields from join where having group order offset limit};
inlineSQL
results
iterate
Calls the given method for each result returned from the current query.
dbh
SEE ALSO
AUTHOR
Tom Molesworth <cpan@entitymodel.com>
LICENSE
Licensed under the same terms as Perl itself.