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Class: SQLite3::ResultSet

Relationships & Source Files
Extension / Inclusion / Inheritance Descendants
Subclasses:
HashResultSet
Super Chains via Extension / Inclusion / Inheritance
Instance Chain:
self, Enumerable
Inherits: Object
Defined in: lib/sqlite3/resultset.rb

Overview

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 Method Summary

Instance Attribute Summary

Instance Method Summary

  • #close

    Closes the statement that spawned this result set.

  • #columns

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

  • #each

    Required by the Enumerable mixin.

  • #each_hash

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

  • #next

    Obtain the next row from the cursor.

  • #next_hash (also: #next)

    Return the next row as a hash.

  • #reset(*bind_params)

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

  • #types

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

Constructor Details

.new(db, stmt) ⇒ ResultSet

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

[ GitHub ] 

  


# File 'lib/sqlite3/resultset.rb', line 14



def initialize db, stmt
  @db = db
  @stmt = stmt
end


  







Instance Attribute Details



  

    #closed?  ⇒ Boolean  (readonly)
  



  

    

Queries whether the underlying statement has been closed or not.


  





  


  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 70



def closed?
  @stmt.closed?
end


  








  

    #eof?  ⇒ Boolean  (readonly)
  



  

    

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


  





  


  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 27



def eof?
  @stmt.done?
end


  







Instance Method Details



  

    #close  
  



  

    

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.


  



  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 65



def close
  @stmt.close
end


  








  

    #columns  
  



  

    

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


  



  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 80



def columns
  @stmt.columns
end


  








  

    #each  
  



  

    

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


  



  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 48



def each
  while (node = self.next)
    yield node
  end
end


  








  

    #each_hash  
  



  

    

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


  



  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 56



def each_hash
  while (node = next_hash)
    yield node
  end
end


  








  

    #next  
  



  

    

Obtain the next row from the cursor. If there are no more rows to be had, this will return nil.



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.


  



  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 42



def next
  @stmt.step
end


  








  

    #next_hash  
    Also known as: #next
  



  

    

Return the next row as a hash


  



  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 85



def next_hash
  row = @stmt.step
  return nil if @stmt.done?

  @stmt.columns.zip(row).to_h
end


  








  

    #reset(*bind_params)  
  



  

    

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


  



  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 21



def reset(*bind_params)
  @stmt.reset!
  @stmt.bind_params(*bind_params)
end


  








  

    #types  
  



  

    

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


  



  [ GitHub ]


  

  


# File 'lib/sqlite3/resultset.rb', line 75



def types
  @stmt.types
end