Database Migration from MySQL to RDM Server - Embedded Tools ...

MIGRATION GUIDEDatabase Migration from MySQLto RDM ServerA Birdstep Technology, Inc. Raima Embedded Database Division Migration GuidePublished: May, 2009Author: Daigoro F. ToyamaSenior Software Engineerdaigoro.toyama@birdstep.comCopyright: Birdstep Technology, Inc. All rights reservedAbstract:This document is designed to act as a quick guide to the database migration from MySQL to RDMServer by exposing the differences between the two products with regards to the data types, featuresand SQL statement syntaxes supported differently between them.This article is relative to the following versions of RDM:In this document, MySQL refers to MySQL 6.0. Likewise, RDM Server (or RDMs) refers toRDM Server 8.2.http://www.raima.com

Migration GuideContents:Abstract: ........................................................................................................................................... 1Contents: .......................................................................................................................................... 2Overview ........................................................................................................................................... 4Data Types........................................................................................................................................ 4Data Definition Language Statements ................................................................................................ 5ALTER DATABASE / SCHEMA ...................................................................................................... 5ALTER EVENT .............................................................................................................................. 5ALTER FUNCTION / PROCEDURE................................................................................................ 5ALTER SERVER............................................................................................................................ 5ALTER TABLE ............................................................................................................................... 6CREATE DATABASE ..................................................................................................................... 6CREATE EVENT ........................................................................................................................... 6CREATE INDEX ............................................................................................................................ 6CREATE FUNCTION / PROCEDURE ............................................................................................. 6CREATE SERVER ......................................................................................................................... 6CREATE TABLE ............................................................................................................................ 7CREATE TRIGGER ....................................................................................................................... 7CREATE VIEW .............................................................................................................................. 7DROP DATABASE / SCHEMA ....................................................................................................... 7DROP EVENT ............................................................................................................................... 7DROP INDEX ................................................................................................................................ 7DROP PROCEDURE / FUNCTION ................................................................................................. 7DROP SERVER ............................................................................................................................. 8DROP TABLE ................................................................................................................................ 8DROP TRIGGER ........................................................................................................................... 8DROP VIEW .................................................................................................................................. 8RENAME TABLE ........................................................................................................................... 8Data Manipulation Language Statements ........................................................................................... 8CALL ............................................................................................................................................. 8DELETE ........................................................................................................................................ 9DO ................................................................................................................................................ 9HANDLER ..................................................................................................................................... 9http://www.raima.comPage | 2

Migration GuideINSERT ......................................................................................................................................... 9LOAD DATA INFILE ....................................................................................................................... 9LOAD XML INFILE ......................................................................................................................... 9REPLACE.................................................................................................................................... 10SELECT ...................................................................................................................................... 10TRUNCATE ................................................................................................................................. 10UPDATE ...................................................................................................................................... 10Transactional and Locking Statements ............................................................................................. 10START TRANSACTION / BEGIN .................................................................................................. 10COMMIT / ROLLBACK ................................................................................................................. 10SET AUTOCOMMIT ..................................................................................................................... 11SAVEPOINT ................................................................................................................................ 11ROLLBACK TO SAVEPOINT ....................................................................................................... 11LOCK / UNLOCK TABLES ........................................................................................................... 11SET TRANSACTION ISOLATION................................................................................................. 11Conclusion ...................................................................................................................................... 11Contact Information ......................................................................................................................... 12http://www.raima.comPage | 3

Migration GuideOverviewThis document gives an overview of the key differences in the SQL implementations between MySQLand RDM Server. It is intended to be a guide for developers to obtain a quick overview of the items totake into consideration when moving an application from MySQL to RDM Server. The first two sectionsof this document outline the differences in the data types and SQL statements that exist between thetwo database solutions. However, it does not outline any of the differences in the native APIs of eachproduct. As long as developers use the standard SQL-API, ODBC and/or JDBC interfaces the matchbetween the two products should be nearly identical. If developers are using the MySQL native C-API atranslation is required to RDM Servers-supported SAG CLI-API. Information on how to do thistranslation can be found at: http://en.wikipedia.org/wiki/Call_Level_Interface.Data TypesThe following table shows the data types supported by MySQL in its data definition language and thecorresponding data types supported by RDM Server when applicable.Data Type MySQL RDM Server8-bit integerBIT16-bit integer SMALLINT SMALLINT24-bit integerMEDIUMINT32-bit integer INT/INTEGER INTEGER64-bit integer BIGINT BIGINT32-bit floating point64-bit floating pointFLOATDOUBLE / REALVariable floating point DECIMAL / NUMERIC DECIMAL / NUMERICDate DATE DATETime TIME TIMEDate and Time DATETIME / TIMESTAMP TIMESTAMPYearYEARCharacter String CHAR / VARCHAR CHAR / VARCHARBinary BINARY / VARBINARY BINARY / VARBINARYhttp://www.raima.comPage | 4

Migration GuideData Type MySQL RDM ServerBLOB (binary) TINYBLOB / BLOB /MEDIUMBLOB / LONGBLOBBLOB (character) TINYTEXT / TEXT /MEDIUMTEXT / LONGTEXTLONG VARBINARYLONG VARCHARCharacter string (enum)Character string (set)ENUMSETData Definition Language StatementsHere is the list of the DDL statements supported by MySQL.ALTER DATABASE / SCHEMAThe ALTER DATABASE statement in MySQL is used to change the overall characteristics of adatabase. It differs from that of RDM Server where the statement is used to change the contents of adatabase (such as adding/dropping tables/indices). RDM Server currently does not support thisfunctionality, but the statement is used mainly for upgrading a MySQL 5.1 database to 6.0.Supported:Necessary:NoNoALTER EVENTThe ALTER EVENT statement in MySQL is used to change the characteristics of an existing event.Since RDM Server does not support events, it naturally does not support this statement.Supported:Necessary:NoALTER FUNCTION / PROCEDUREThe ALTER FUNCTION / PROCEDURE statement in MySQL is used to change the characteristics of astored function or stored procedure. RDM Server supports functions and procedures but does not allowthe alternation of their characteristics.Supported:Necessary:NoALTER SERVERThe ALTER SERVER statement in MySQL is used to change the information on the specified server.RDM Server does not support the concept of creating/altering servers.Supported:Necessary:NoNohttp://www.raima.comPage | 5

Migration GuideALTER TABLEThe ALTER TABLE statement in MySQL is used to change the structure of an existing table. RDMServer supports most of the core options, such as adding/dropping indices, adding/dropping/alteringcolumns, and renaming columns. Those we do not support are mostly for the features that we do notsupport.Supported:Necessary:YesYesCREATE DATABASEThe CREATE DATABASE statement in MySQL creates a new database. MySQL and RDM Serversupports different options as they support different database features. For instance, MySQL allows theuser to set the default database character set and collation name.Supported:Necessary;YesYesCREATE EVENTThe CREATE EVENT statement in MySQL creates and schedules a new event. RDM Server does notsupport events; therefore not CREATE EVENT.Supported:Necessary:NoNoCREATE INDEXThe CREATE INDEX statement in MySQL is used to create an index. RDM Server supports it exceptfor the USING [ BTREE | HASH | RTREE ] clause that specifies the indexing algorithm (we only useBTREE) and the WITH PARSER clause.Supported:Necessary:YesYesCREATE FUNCTION / PROCEDUREThe CREATE FUNCTION / PROCEDURE statement in MySQL is used to create a function or a storedprocedure. RDM Server supports both, though the details differ. MySQL lets you create both functionsand procedures in SQL; RDM Server requires that functions and user-defined procedures be written asshared librariesSupported:Necessary:YesYesCREATE SERVERThe CREATE SERVER statement in MySQL creates the definition of a server. RDM Server does notsupport it as our concept of a server is different than that of MySQL.Supported:Necessary:NoNohttp://www.raima.comPage | 6

Migration GuideDROP SERVERThe DROP SERVER statement in MySQL drops a server definition. RDM Server does not support it asour concept of a server is different than that of MySQL.DROP TABLEThe DROP TABLE statement in MySQL removes one or more tables. Triggers for the dropped table(s)will also be dropped. RDM Server supports DROP TABLE, though only one table can be removed at atime. RDM Server does not support the IF EXISTS extension, either.Supported:Necessary;YesYesDROP TRIGGERThe DROP TRIGGER statement in MySQL drops a trigger. RDM Server supports triggers in the form ofUDF, but not in this ANSI format.Supported:Necessary:NoProbablyDROP VIEWThe DROP VIEW statement in MySQL drops one or more views. RDM Server supports DROP VIEW,though only one view can be removed at a time. RDM Server does not support the IF EXISTSextension, either.Supported:Necessary:Yes, basicallyYesRENAME TABLEThe RENAME TABLE statement in MySQL renames one or more tables. RDM Server supportsRENAME TABLE with a slightly different syntax. It also only supports renaming one table at a time.Supported:Necessary:Yes, basicallyYesData Manipulation Language StatementsHere is the list of the DML statements supported by MySQL.CALLThe CALL statement in MySQL invokes a stored procedure. The RDM Server equivalent is EXECUTE.Supported:Necessary:YesYeshttp://www.raima.comPage | 8

Migration GuideDELETEThe DELETE statement in MySQL deletes rows from the specified table and returns a count of thenumber of deleted rows. MySQL extends the statement with keywords such as QUICK (where theindex leaves are not merged during DELETE) and LIMIT (which limits the number of rows to delete).RDM Server supports the core DELETE statement, but not those MySQL extensions.Supported:Necessary:YesYesDOThe DO statement in MySQL executes the expressions but does not return any results. RDM Serverdoes not support it.Supported:Necessary:NoNoHANDLERThe HANDLER statement in MySQL provides direct access to table storage engine interfaces. It isavailable for MyISAM and InnoDB tables. Naturally, RDM Server does not support it.Supported:Necessary:NoNoINSERTThe INSERT statement in MySQL inserts new rows into an existing table. The INSERT … VALUESstatement works identically to that of RDM Server. The INSERT … SET statement can be replacedeasily with INSERT … VALUES with specific column names. RDM Server does not support MySQLextensions such as INSERT DELAYED and INSERT IGNORE.Supported:Necessary;YesYesLOAD DATA INFILEThe LOAD DATA INFILE statement in MySQL reads rows from a text file into a table. The RDM Serverequivalent is INSERT … FROM (ASCII) FILE. The LOAD DATA INFILE statement allows for moreflexibility than our INSERT … FROM FILE when selecting particular sections of the file to be read andinserted.Supported:Necessary:YesYesLOAD XML INFILEThe LOAD XML INFILE statement in MySQL reads data from an XML file into a table. The RDM Serverequivalent is INSERT … FROM XML FILE. The same issue with flexibility found in LOAD DATA INFILEexists here.Supported:Necessary;YesYeshttp://www.raima.comPage | 9

Migration GuideREPLACEThe REPLACE statement in MySQL works exactly like INSERT, except that if an old row has the samevalue as a new row for a PRIMARY / UNIQUE KEY index, the old row is deleted before the new row isinserted.It means the REPLACE statement is a combination of INSERT and UPDATE. RDM Server does notsupport this specific syntax, but the same result can be achieved by combining SELECT, INSERT andUPDATE. A UDP would be an option, too.Supported:Necessary:No, but it can be worked aroundNoSELECTThe SELECT statement in MySQL is used to retrieve rows from one or more tables. MySQL allowsUNION, JOIN and sub queries. RDM Server supports it except for a few fine-tuning parameters andUNION. The UNION syntax will be supported in the next version of RDM Server. MySQL also allowsindex hints to be specified for manual query optimization. RDM Server supports the same conceptthrough a different syntax.Supported:Necessary:Yes, except for UNIONYesTRUNCATEThe TRUNCATE [TABLE] statement in MySQL empties a table completely. RDM Server does notsupport this, although DELETE FROM TABLE syntactically serves the same purpose. TheTRUNCATE statement in MySQL exists primarily for performance purposes.Supported:Necessary:NoNoUPDATEThe UPDATE statement in MySQL updates rows in one or more tables with the specified new values.RDM Server supports it except for the IGNORE and LIMIT extensions.Supported:Necessary:Yes, basicallyYesTransactional and Locking StatementsHere is the list of the transactional and locking statements supported by MySQL.START TRANSACTION / BEGINThe START TRANSACTION or BEGIN statement in MySQL begins a new transaction. RDM Serversupports the operation with the BEGIN [WORK] statement.COMMIT / ROLLBACKThe COMMIT / ROLLBACK statement in MySQL commits / rolls back the current transaction. RDMServer supports the operations with the COMMIT / ROLLBACK statements.http://www.raima.comPage | 10

Migration GuideSET AUTOCOMMITThe SET AUTOCOMMIT statement in MySQL turns on or off the automatic commit mode. Theautomatic commit mode is ON by default in MySQL. You run the statement in the following way todisable auto commit.SET autocommit = 0;RDM Server does not support the SET AUTOCOMMIT statement directly, though it should not be hardto add support for it. RDM Server also supports the INSERT statement with the WITH AUTO COMMIToption as follows.INSERT WITH AUTO COMMIT INTO table_name VALUES( … );SAVEPOINTThe SAVEPOINT statement in MySQL, when used with InnoDB or Falcon, sets a named transactionsave point with a name. If the current transaction has a save point with the same name, the old savepoint is deleted and a new one is set. RDM Server supports this feature with the MARK statement. Thebehaviour is identical.ROLLBACK TO SAVEPOINTThe ROLLBACK TO SAVEPOINT statement in MySQL rolls back a transaction to the named save pointwithout terminating the transaction. The locks applied after the save point will be freed under Falcon butnot under InnoDB. RDM Server supports this feature with the same syntax. Its behaviour regarding thelocks is identical to that of InnoDB.LOCK / UNLOCK TABLESThe LOCK / UNLOCK TABLES statements in MySQL acquires / releases non-transactional andtransactional table locks. The LOCK / UNLOCK TABLE statements can be used on views as well astables. RDM Server supports this feature with the LOCK / UNLOCK TABLE statements, though it doesnot support locking / unlocking views.SET TRANSACTION ISOLATIONThe SET TRANSACTION ISOLATION statement in MySQL sets the transaction isolation level globally,for the current session or for the next transaction. All modes – READ COMMITTED, READUNCOMMITTED, REPEATABLE READ and SERIALIZE are supported. RDM Server supports thisfeature as well, sans SERIALIZE. RDM Server also only supports the transaction isolation setting onthe current session.ConclusionWith RDM Server’s support for SQL being nearly the same as that of MySQL’s and RDM Server’sability to run as a embedded library like MySQL, moving an embedded application over to RDM Serveris relatively easy. So why not take advantage of the additional benefits in RDM Server’s performance,full transactional support, and competitive licensing options.http://www.raima.comPage | 11

Migration GuideContact InformationWebsite: http://www.raima.comNORTH AMERICAEUROPEBirdstep Technology, Inc.Birdstep Technology ASA2101 Fourth Avenue, Suite 240 C.J. Hambros Plass 3cSeattle, WA 981210164 Oslo, NorwayTelephone: +1 206 748 5300 Telephone: +47 90628326Fax: +1 206 748 5200 Fax: +47 24134701E-mail: americas@birdstep.comE-mail: lpagni@birdstep.comhttp://www.raima.comPage | 12