objects are all updated, and the time to update memory structures such as the buffer pool . For a table , the drop operation has somewhat different characteristics than a truncate  operation ( TRUNCATE TABLE  statement). 

See Also buffer pool, data dictionary, DDL, table, truncate. 

## DSN 

 Acronym for “Database Source Name” . It is the encoding for connection  information within Connector/ODBC . See Configuring a Connector/ODBC DSN on Windows for full details. It is the equivalent of the connection string  used by Connector/NET . 

See Also connection, connection string, Connector/NET, Connector/ODBC. 

## dynamic cursor 

 A type of cursor  supported by ODBC  that can pick up new and changed results when the rows are read again. Whether and how quickly the changes are visible to the cursor depends on the type of table involved (transactional or non-transactional) and the isolation level for transactional tables. Support for dynamic cursors must be explicitly enabled. 

See Also cursor, ODBC. 

## dynamic row format 

 An InnoDB  row format. Because long variable-length column values are stored outside of the page that holds the row data, it is very efficient for rows that include large objects. Since the large fields are typically not accessed to evaluate query conditions, they are not brought into the buffer pool  as often, resulting in fewer I/O operations and better utilization of cache memory. 

As of MySQL 5.7.9, the default row format is defined by innodb_default_row_format , which has a default value of DYNAMIC . 

For additional information about InnoDB DYNAMIC  row format, see DYNAMIC Row Format. 

See Also buffer pool, file format, row format. 

## dynamic SQL 

 A feature that lets you create and execute prepared statements  using more robust, secure, and efficient methods to substitute parameter values than the naive technique of concatenating the parts of the statement into a string variable. 

See Also prepared statement. 

## dynamic statement 

 A prepared statement  created and executed through dynamic SQL . 

See Also dynamic SQL, prepared statement. 

## E 

## early adopter 

 A stage similar to beta , when a software product is typically evaluated for performance, functionality, and compatibility in a non-mission-critical setting. 

See Also beta. 

## Eiffel 

 A programming language including many object-oriented features. Some of its concepts are familiar to Java  and C#  developers. For the open-source Eiffel API  for MySQL, see Section 29.13, “MySQL Eiffel Wrapper” . 

See Also API, C#, Java. 

## embedded 

 The embedded MySQL server library ( libmysqld ) makes it possible to run a full-featured MySQL server inside a client  application. The main benefits are increased speed and more simple management for embedded applications. 

See Also client, libmysqld. 

