class SQLite3::ResultSet

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 SQLite3::Statement#execute.

Public Class Methods

new(db, stmt) click to toggle source

Create a new ResultSet attached to the given database, using the given sql text.

# File lib/sqlite3/resultset.rb, line 72
def initialize db, stmt
  @db   = db
  @stmt = stmt
end

Public Instance Methods

close() click to toggle source

Closes the statement that spawned this result set. Use with caution! Closing a result set will automatically close any other result sets that were spawned from the same statement.

# File lib/sqlite3/resultset.rb, line 149
def close
  @stmt.close
end

closed?() click to toggle source

Queries whether the underlying statement has been closed or not.

# File lib/sqlite3/resultset.rb, line 154
def closed?
  @stmt.closed?
end

columns() click to toggle source

Returns the names of the columns returned by this result set.

# File lib/sqlite3/resultset.rb, line 164
def columns
  @stmt.columns
end

each() { |node| ... } click to toggle source

Required by the Enumerable mixin. Provides an internal iterator over the rows of the result set.

# File lib/sqlite3/resultset.rb, line 132
def each
  while node = self.next
    yield node
  end
end

each_hash() { |node| ... } click to toggle source

Provides an internal iterator over the rows of the result set where each row is yielded as a hash.

# File lib/sqlite3/resultset.rb, line 140
def each_hash
  while node = next_hash
    yield node
  end
end

eof?() click to toggle source

Query whether the cursor has reached the end of the result set or not.

# File lib/sqlite3/resultset.rb, line 86
def eof?
  @stmt.done?
end

next() click to toggle source

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 SQLite3::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.

# File lib/sqlite3/resultset.rb, line 103
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

next_hash() click to toggle source

Return the next row as a hash

# File lib/sqlite3/resultset.rb, line 169
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

reset( *bind_params ) click to toggle source

Reset the cursor, so that a result set which has reached end-of-file can be rewound and reiterated.

# File lib/sqlite3/resultset.rb, line 79
def reset( *bind_params )
  @stmt.reset!
  @stmt.bind_params( *bind_params )
  @eof = false
end

types() click to toggle source

Returns the types of the columns returned by this result set.

# File lib/sqlite3/resultset.rb, line 159
def types
  @stmt.types
end