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 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 49
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 115
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 120
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 131
def columns
  must_be_open!
  @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 97
def each
  must_be_open!
  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 106
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 64
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 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 81
def next
  must_be_open!
  if @db.results_as_hash
    return next_hash
  end

  row = @stmt.step
  return nil if @stmt.done?
  row = ArrayWithTypesAndFields.new(row)
  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 137
def next_hash
  must_be_open!
  row = @stmt.step
  return nil if @stmt.done?

  # 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 56
def reset( *bind_params )
  must_be_open!
  @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 125
def types
  must_be_open!
  @stmt.types
end

Private Instance Methods

must_be_open!() click to toggle source
# File lib/sqlite3/resultset.rb, line 154
def must_be_open!
  raise Exception, "#{self.class} is closed!" if closed?
end