DB2 UDB supports all the features supported by MySQL with same kind of 

terminologies. So, they map directly while migrating.

Create Index

The following is a MySQL create index statement:

CREATE [UNIQUE|FULLTEXT] INDEX index_name [index_type]

ON tbl_name (index_col_name,...)

index_col_name:

col_name [(length)] [ASC | DESC]

Creating an index in DB2 UDB is quite similar. It can be done using:

CREATE [unique] INDEX index name on tablename (columnnames ASC|DESC)

  SPECIFICATION ONLY INCLUDE(column name)

  CLUSTER/EXTEND USING index extension name (constant expression)

  PCTFREE 10/PCTFREE integer LEVEL PCTFREE integer MINPCTUSED integer

  ALLOW/DISALLOW REVERSE SCANS

  PAGE SPLIT SYMMETRIC/PAGE SPLIT HIGH/LOW

  COLLECT STATISTICS DETAILED SAMPLED

Drop index

Drop index statement for MySQL and DB2 UDB:

mysql>DROP INDEX index_name ON tbl_name;

db2>DROP INDEX index_name

5.3  Other considerations

Up until now we discussed approaches for converting database elements, which 

use similar approaches in two products. In the subsequent sections we discuss 

conversion of the database objects, which does not map directly in MySQL and 

DB2 UDB. We also discuss server and database placement architecture.

Multiple servers

In some cases multiple MySQL servers are placed on the same machine. It may 

be for the reason of user management or testing, or differentiating applications 

and keeping them independent. MySQL provides an option to run multiple 

servers on same machine using several operating parameters.

There are several ways to configure new server; we used: 

bash> /path/to/mysqld   socket=file_name   port=port_number

or you can use:

bash> MYSQL_UNIX_PORT=/tmp/mysqld new.sock

 Chapter 5. Database porting 

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