JezK
Edit File: resultset.rb
require 'sqlite3/constants' require 'sqlite3/errors' module SQLite3 # The ResultSet object encapsulates the enumerability of a query's output. # It is a simple cursor over the data that the query returns. It will # very rarely (if ever) be instantiated directly. Instead, clients should # obtain a ResultSet instance via Statement#execute. class ResultSet include Enumerable class ArrayWithTypes < Array # :nodoc: attr_accessor :types end class ArrayWithTypesAndFields < Array # :nodoc: attr_writer :types attr_writer :fields def types warn(<<-eowarn) if $VERBOSE #{caller[0]} is calling #{self.class}#types. This method will be removed in sqlite3 version 2.0.0, please call the `types` method on the SQLite3::ResultSet object that created this object eowarn @types end def fields warn(<<-eowarn) if $VERBOSE #{caller[0]} is calling #{self.class}#fields. This method will be removed in sqlite3 version 2.0.0, please call the `columns` method on the SQLite3::ResultSet object that created this object eowarn @fields end end # The class of which we return an object in case we want a Hash as # result. class HashWithTypesAndFields < Hash # :nodoc: attr_writer :types attr_writer :fields def types warn(<<-eowarn) if $VERBOSE #{caller[0]} is calling #{self.class}#types. This method will be removed in sqlite3 version 2.0.0, please call the `types` method on the SQLite3::ResultSet object that created this object eowarn @types end def fields warn(<<-eowarn) if $VERBOSE #{caller[0]} is calling #{self.class}#fields. This method will be removed in sqlite3 version 2.0.0, please call the `columns` method on the SQLite3::ResultSet object that created this object eowarn @fields end def [] key key = fields[key] if key.is_a? Numeric super key end end # Create a new ResultSet attached to the given database, using the # given sql text. def initialize db, stmt @db = db @stmt = stmt end # Reset the cursor, so that a result set which has reached end-of-file # can be rewound and reiterated. def reset( *bind_params ) @stmt.reset! @stmt.bind_params( *bind_params ) @eof = false end # Query whether the cursor has reached the end of the result set or not. def eof? @stmt.done? end # Obtain the next row from the cursor. If there are no more rows to be # had, this will return +nil+. If type translation is active on the # corresponding database, the values in the row will be translated # according to their types. # # The returned value will be an array, unless Database#results_as_hash has # been set to +true+, in which case the returned value will be a hash. # # For arrays, the column names are accessible via the +fields+ property, # and the column types are accessible via the +types+ property. # # For hashes, the column names are the keys of the hash, and the column # types are accessible via the +types+ property. def next if @db.results_as_hash return next_hash end row = @stmt.step return nil if @stmt.done? row = @db.translate_from_db @stmt.types, row if row.respond_to?(:fields) # FIXME: this can only happen if the translator returns something # that responds to `fields`. Since we're removing the translator # in 2.0, we can remove this branch in 2.0. row = ArrayWithTypes.new(row) else # FIXME: the `fields` and `types` methods are deprecated on this # object for version 2.0, so we can safely remove this branch # as well. row = ArrayWithTypesAndFields.new(row) end row.fields = @stmt.columns row.types = @stmt.types row end # Required by the Enumerable mixin. Provides an internal iterator over the # rows of the result set. def each while node = self.next yield node end end # Provides an internal iterator over the rows of the result set where # each row is yielded as a hash. def each_hash while node = next_hash yield node end end # Closes the statement that spawned this result set. # <em>Use with caution!</em> Closing a result set will automatically # close any other result sets that were spawned from the same statement. def close @stmt.close end # Queries whether the underlying statement has been closed or not. def closed? @stmt.closed? end # Returns the types of the columns returned by this result set. def types @stmt.types end # Returns the names of the columns returned by this result set. def columns @stmt.columns end # Return the next row as a hash def next_hash row = @stmt.step return nil if @stmt.done? # FIXME: type translation is deprecated, so this can be removed # in 2.0 row = @db.translate_from_db @stmt.types, row # FIXME: this can be switched to a regular hash in 2.0 row = HashWithTypesAndFields[*@stmt.columns.zip(row).flatten] # FIXME: these methods are deprecated for version 2.0, so we can remove # this code in 2.0 row.fields = @stmt.columns row.types = @stmt.types row end end end