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Migrating and upgrading
You can upgrade to the 14.10 release of HCL Informix® or migrate from other database servers to Informix. Upgrading is an in-place migration method that uses your existing hardware and operating system software. Some changes to the Informix database server can affect upgrading from a previous release.
Migrating Informix® database systems
The Informix® Migration Guide describes how to move data manually between databases, servers, and computers.
Data migration utilities
The dbexport and dbimport utilities
The dbexport and dbimport utilities import and export a database and its schema to disk or tape.
Simple large objects
When the dbimport, dbexport, and DB-Access utilities process simple-large-object data, they create temporary files for that data in a temporary directory.

Migrating and upgrading
You can upgrade to the 14.10 release of HCL Informix® or migrate from other database servers to Informix. Upgrading is an in-place migration method that uses your existing hardware and operating system software. Some changes to the Informix database server can affect upgrading from a previous release.
- Migrating Informix® database systems
  The Informix® Migration Guide describes how to move data manually between databases, servers, and computers.
  - Overview of migration
  - Migration to and reversion from 14.10
  - Migration of data between database servers
  - Data migration utilities
    - External tables
      External tables are a fast and versatile method for moving data between database servers. External tables are the fastest method for loading data into a RAW table with no indexes.
    - The dbexport and dbimport utilities
      The dbexport and dbimport utilities import and export a database and its schema to disk or tape.
      - Syntax of the dbexport Command
        The dbexport command unloads a database into text files that you can later import into another database. The command also creates a schema file.
      - Contents of the schema file that dbexport creates
        The dbexport utility creates a schema file. This file contains the SQL statements that you need to re-create the exported database.
      - Syntax of the dbimport command
        The dbimport command imports previously exported data into another database.
      - Changing the database locale with dbimport
        You can use the dbimport utility to change the locale of a database.
      - Simple large objects
        When the dbimport, dbexport, and DB-Access utilities process simple-large-object data, they create temporary files for that data in a temporary directory.
    - The dbload utility
      The dbload utility loads data into databases or tables that Informix® products created. It transfers data from one or more text files into one or more existing tables.
    - The dbschema utility
      The dbschema utility displays the SQL statements (the schema) that are necessary to replicate database objects.
    - The LOAD and UNLOAD statements
      You can use the SQL LOAD and UNLOAD statements to move data. The LOAD statement is moderately fast and easy to use, but it only accepts specified data formats. You usually use the LOAD statement with data that is prepared with an UNLOAD statement.
    - The onunload and onload utilities
      The onunload and onload utilities provide the fastest way to move data between computers that use the same database server on the same platform.
    - The onmode utility reversion option
      You use the -b option of the onmode utility to revert to the older database server from which you converted.
    - The onrestorept utility
      You can use the onrestorept utility to restore the database server back to the state that it was in just before the start of the failed upgrade.

Simple large objects

When the dbimport, dbexport, and DB-Access utilities process simple-large-object data, they create temporary files for that data in a temporary directory.

Before you export or import data from tables that contain simple large objects, you must have one of the following items:

A \tmp directory on your currently active drive
The DBTEMP environment variable set to point to a directory that is available for temporary storage of the simple large objects

Windows™ Only: Windows™ sets the TMP and TEMP environment variables in the command prompt sessions, by default. However, if the TMP, TEMP, and DBTEMP environment variables are not set, dbimport places the temporary files for the simple large objects in the \tmp directory.

Attention: If a table has a CLOB or BLOB in a column, you cannot use dbexport to export the table to a tape. If a table has a user-defined type in a column, using dbexport to export the table to a tape might yield unpredictable results, depending on the export function of the user-defined type. Exported CLOB sizes are stored in hex format in the unload file.