# Io Reference

Databases / QDBM / QDBM

|  | An ordered key/value database that supports transactions and arbitrary kay and value sizes.
|  | abort Abort transaction. Returns self at(keySymbol) Returns a Sequence for the value at the given key or nil if there is no such key. atPut(keySymbol, valueSequence) Sets the value of valueSequence with the key keySymbol. Returns self. atRemove(keySymbol) Removes the specified key. Returns self begin Begin transaction. Returns self close Closes the database. commit Commit transaction. Returns self cursorFirst Move cursor to first record. Returns self cursorJumpBackward(key) Move cursor to previous record around key. Returns self cursorJumpForward(key) Move cursor to next record around key. Returns self cursorKey Returns current cursor key or nil. cursorLast Move cursor to last record. Returns self cursorNext Move cursor to next record. Returns true if there is another key, or false if there is no next record. cursorPrevious Move cursor to previous record. Returns true if there is another key, or false if there is no previous record. cursorPut(value) Sets the value at the current cursor postion. Returns self. cursorRemove Removes the current cursor postion. Returns self. cursorValue Returns current cursor value or nil. name Returns the name of the database. open(path) Opens the database. optimize Optimizes the database. Returns self size Returns number of records in database. Returns self sizeAt(keySymbol) Returns the size of the value at the given key or nil if there is no such key. sync Syncs the database. Returns self