RDF::QUERY::COMPILER::SQL - reference manual online
Compile a SPARQL query directly to SQL.
RDF::Query::Compiler::SQL(3pm) User Contributed Perl Documentation RDF::Query::Compiler::SQL(3pm)
NAME RDF::Query::Compiler::SQL - Compile a SPARQL query directly to SQL. VERSION This document describes RDF::Query::Compiler::SQL version 2.916. STATUS This module's API and functionality should be considered deprecated. If you need functionality that this module provides, please get in touch <http://www.perlrdf.org/>. METHODS "new ( $parse_tree )" Returns a new compiler object. "compile ()" Returns a SQL query string for the specified parse tree. "emit_select" Returns a SQL query string representing the query. "limit_clause" Returns a SQL LIMIT clause, or an empty string if the query does not need limiting. "order_by_clause" Returns a SQL ORDER BY clause, or an empty string if the query does not use ordering. "variable_columns ( $var )" Given a variable name, returns the set of column aliases that store the values for the column (values for Literals, URIs, and Blank Nodes). "add_variable_values_joins" Modifies the query by adding LEFT JOINs to the tables in the database that contain the node values (for literals, resources, and blank nodes). "patterns2sql ( \@triples, \$level, %args )" Builds the SQL query in instance data from the supplied @triples. $level is used as a unique identifier for recursive calls. %args may contain callback closures for the following keys: 'where_hook' 'from_hook' When present, these closures are used to add SQL FROM and WHERE clauses to the query instead of adding them directly to the object's instance data. "expr2sql ( $expression, \$level, %args )" Returns a SQL expression for the supplied query $expression. $level is used as a unique identifier for recursive calls. %args may contain callback closures for the following keys: 'where_hook' 'from_hook' When present, these closures are used to add necessary SQL FROM and WHERE clauses to the query. "_mysql_hash ( $data )" Returns a hash value for the supplied $data string. This value is computed using the same algorithm that Redland's mysql storage backend uses. "_mysql_node_hash ( $node )" Returns a hash value (computed by "_mysql_hash" for the supplied $node. The hash value is based on the string value of the node and the node type. "qualify_uri ( $uri )" Returns a fully qualified URI from the supplied $uri. $uri may already be a qualified URI, or a parse tree for a qualified URI or QName. If $uri is a QName, the namespaces defined in the query parse tree are used to fully qualify. "add_function ( $uri, $function )" Associates the custom function $function (a CODE reference) with the specified URI, allowing the function to be called by query FILTERs. "get_function ( $uri )" If $uri is associated with a query function, returns a CODE reference to the function. Otherwise returns "undef".perl v5.20.2 2015-10-16 RDF::Query::Compiler::SQL(3pm)