Class: Sequel::SQLite::Dataset

Inherits:
Dataset show all
Includes:
DatasetMethods
Defined in:
lib/sequel/adapters/sqlite.rb

Overview

Dataset class for SQLite datasets that use the ruby-sqlite3 driver.

Defined Under Namespace

Modules: ArgumentMapper, PreparedStatementMethods

Constant Summary collapse

EXPLAIN = 
'EXPLAIN %s'.freeze
PREPARED_ARG_PLACEHOLDER = 
':'.freeze

Constants included from DatasetMethods

Sequel::SQLite::DatasetMethods::SELECT_CLAUSE_ORDER

Constants inherited from Dataset

Dataset::AND_SEPARATOR, Dataset::ARRAY_ACCESS_ERROR_MSG, Dataset::BOOL_FALSE, Dataset::BOOL_TRUE, Dataset::COLUMN_CHANGE_OPTS, Dataset::COLUMN_REF_RE1, Dataset::COLUMN_REF_RE2, Dataset::COLUMN_REF_RE3, Dataset::COMMA_SEPARATOR, Dataset::COUNT_FROM_SELF_OPTS, Dataset::COUNT_OF_ALL_AS_COUNT, Dataset::DATASET_ALIAS_BASE_NAME, Dataset::GET_ERROR_MSG, Dataset::IMPORT_ERROR_MSG, Dataset::INSERT_SQL_BASE, Dataset::IS_LITERALS, Dataset::IS_OPERATORS, Dataset::MAP_ERROR_MSG, Dataset::MUTATION_METHODS, Dataset::NOTIMPL_MSG, Dataset::NULL, Dataset::N_ARITY_OPERATORS, Dataset::QUALIFY_KEYS, Dataset::QUESTION_MARK, Dataset::SELECT_CLAUSE_ORDER, Dataset::SQL_WITH, Dataset::STOCK_COUNT_OPTS, Dataset::TWO_ARITY_OPERATORS, Dataset::WILDCARD, Dataset::WITH_SUPPORTED

Instance Attribute Summary

Attributes inherited from Dataset

#db, #identifier_input_method, #identifier_output_method, #opts, #quote_identifiers, #row_proc

Instance Method Summary collapse

Methods included from DatasetMethods

#complex_expression_sql, #delete, #insert, #insert_sql, #quoted_identifier, #supports_intersect_except_all?, #supports_is_true?

Methods inherited from Dataset

#<<, #[], #[]=, #add_graph_aliases, #aliased_expression_sql, #all, #and, #array_sql, #as, #avg, #case_expression_sql, #cast_sql, #clone, #column_all_sql, #columns, #columns!, #complex_expression_sql, #count, def_mutation_method, #def_mutation_method, #delete, #delete_sql, #distinct, #each, #each_page, #empty?, #except, #exclude, #exists, #filter, #first, #first_source_alias, #from, #from_self, #function_sql, #get, #graph, #grep, #group, #group_and_count, #having, #import, #initialize, #insert, #insert_multiple, #insert_sql, #inspect, #intersect, #interval, #invert, #join_clause_sql, #join_on_clause_sql, #join_table, #join_using_clause_sql, #last, #limit, #literal, #map, #max, #min, #multi_insert, #multi_insert_sql, #naked, #or, #order, #order_more, #ordered_expression_sql, #paginate, #placeholder_literal_string_sql, #print, #qualified_identifier_sql, #qualify, #qualify_to, #qualify_to_first_source, #query, #quote_identifier, #quote_identifiers?, #quote_schema_table, #quoted_identifier, #range, #requires_sql_standard_datetimes?, #reverse_order, #schema_and_table, #select, #select_all, #select_more, #select_sql, #server, #set, #set_defaults, #set_graph_aliases, #set_overrides, #single_record, #single_value, #sql, #subscript_sql, #sum, #supports_cte?, #supports_distinct_on?, #supports_intersect_except?, #supports_intersect_except_all?, #supports_is_true?, #supports_window_functions?, #to_csv, #to_hash, #unfiltered, #ungraphed, #union, #unordered, #update, #update_sql, #where, #window_function_sql, #window_sql, #with, #with_recursive, #with_sql

Methods included from Metaprogramming

#meta_def

Constructor Details

This class inherits a constructor from Sequel::Dataset

Instance Method Details

#call(type, hash, values = nil, &block) ⇒ Object

Prepare an unnamed statement of the given type and call it with the given values.



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# File 'lib/sequel/adapters/sqlite.rb', line 177

def call(type, hash, values=nil, &block)
  prepare(type, nil, values).call(hash, &block)
end

#explain ⇒ Object

Return an array of strings specifying a query explanation for the current dataset.



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# File 'lib/sequel/adapters/sqlite.rb', line 183

def explain
  res = []
  @db.result_set(EXPLAIN % select_sql(opts), nil) {|r| res << r}
  res
end

#fetch_rows(sql) ⇒ Object

Yield a hash for each row in the dataset.



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# File 'lib/sequel/adapters/sqlite.rb', line 190

def fetch_rows(sql)
  execute(sql) do |result|
    i = -1
    cols = result.columns.map{|c| [output_identifier(c), i+=1]}
    @columns = cols.map{|c| c.first}
    result.each do |values|
      row = {}
      cols.each{|n,i| row[n] = values[i]}
      yield row
    end
  end
end

#prepare(type, name = nil, values = nil) ⇒ Object

Prepare the given type of query with the given name and store it in the database. Note that a new native prepared statement is created on each call to this prepared statement.



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# File 'lib/sequel/adapters/sqlite.rb', line 206

def prepare(type, name=nil, values=nil)
  ps = to_prepared_statement(type, values)
  ps.extend(PreparedStatementMethods)
  db.prepared_statements[name] = ps if name
  ps
end