module Sequel::Sequel3DatasetMethods

Update all records matching the conditions with the values specified. Returns the number of rows affected.

DB[:table][:id=>1] = {:id=>2} # UPDATE table SET id = 2 WHERE id = 1
# => 1 # number of rows affected

# File lib/sequel/extensions/sequel_3_dataset_methods.rb, line 37
def []=(conditions, values)
  filter(conditions).update(values)
end

Inserts multiple values. If a block is given it is invoked for each item in the given array before inserting it. See multi_insert as a possibly faster version that may be able to insert multiple records in one SQL statement (if supported by the database). Returns an array of primary keys of inserted rows.

DB[:table].insert_multiple([{:x=>1}, {:x=>2}])
# => [4, 5]
# INSERT INTO table (x) VALUES (1)
# INSERT INTO table (x) VALUES (2)

DB[:table].insert_multiple([{:x=>1}, {:x=>2}]){|row| row[:y] = row[:x] * 2; row }
# => [6, 7]
# INSERT INTO table (x, y) VALUES (1, 2)
# INSERT INTO table (x, y) VALUES (2, 4)

# File lib/sequel/extensions/sequel_3_dataset_methods.rb, line 56
def insert_multiple(array, &block)
  if block
    array.map{|i| insert(block.call(i))}
  else
    array.map{|i| insert(i)}
  end
end

Return a copy of the dataset with unqualified identifiers in the SELECT, WHERE, GROUP, HAVING, and ORDER clauses qualified by the given table. If no columns are currently selected, select all columns of the given table.

DB[:items].filter(:id=>1).qualify_to(:i)
# SELECT i.* FROM items WHERE (i.id = 1)

# File lib/sequel/extensions/sequel_3_dataset_methods.rb, line 71
def qualify_to(table)
  qualify(table)
end

Qualify the dataset to its current first source. This is useful if you have unqualified identifiers in the query that all refer to the first source, and you want to join to another table which has columns with the same name as columns in the current dataset. See qualify_to.

DB[:items].filter(:id=>1).qualify_to_first_source
# SELECT items.* FROM items WHERE (items.id = 1)

# File lib/sequel/extensions/sequel_3_dataset_methods.rb, line 83
def qualify_to_first_source
  qualify
end

Alias for update, but not aliased directly so subclasses don’t have to override both methods.

# File lib/sequel/extensions/sequel_3_dataset_methods.rb, line 89
def set(*args)
  update(*args)
end

Returns a string in CSV format containing the dataset records. By default the CSV representation includes the column titles in the first line. You can turn that off by passing false as the include_column_titles argument.

This does not use a CSV library or handle quoting of values in any way. If any values in any of the rows could include commas or line endings, you shouldn’t use this.

puts DB[:table].to_csv # SELECT * FROM table
# id,name
# 1,Jim
# 2,Bob

# File lib/sequel/extensions/sequel_3_dataset_methods.rb, line 106
def to_csv(include_column_titles = true)
  n = naked
  cols = n.columns
  csv = ''
  csv << "#{cols.join(COMMA)}\r\n" if include_column_titles
  n.each{|r| csv << "#{cols.collect{|c| r[c]}.join(COMMA)}\r\n"}
  csv
end