What's new in migration for Informix, Version 12.10

Due to new features and functionality, Informix version 12.10.xC8 contains the following new configuration parameter and environment variables:

• DISK_ENCRYPTION configuration parameter
• USE_SHARDING session environment variable
• IFX_LO_READONLY environment variable

Environment variable changes by version

Due to new features and functionality, Informix version 12.10.xC6 contains the following new configuration parameters and environment variable:

• BAR_MAX_RESTORE configuration parameter
• IFXGUARD configuration parameter
• SHARD_ID configuration parameter
• SHARD_MEM configuration parameter
• SMX_NUMPIPES configuration parameter
• TENANT_LIMIT_CONNECTIONS configuration parameter
• TENANT_LIMIT_MEMORY configuration parameter
• IFX_SOC_KEEPALIVE environment variable

Environment variable changes by version

SQL keyword changes by version

Due to new features and functionality, Informix 12.10.xC5 contains the following changed and new configuration parameters and environment option:

• Changed configuration parameter: AUTO_REPREPARE
• Changed configuration parameter: TAPESIZE
• Changed configuration parameter: LTAPESIZE
• Changed session environment option: IFX_AUTO_REPREPARE
• New configuration parameter: TENANT_LIMIT_SPACE
• New configuration parameter: SESSION_LIMIT_MEMORY
• New configuration parameter: SESSION_LIMIT_TEMPSPACE
• New configuration parameter: SESSION_LIMIT_LOGSPACE
• New configuration parameter: SESSION_LIMIT_TXN_TIME

Environment variable changes by version

SQL keyword changes by version

HCL Informix 12.10.xC5 software supports Java Platform Standard Edition (Java SE), Version 7.

Informix installation applications install IBM® Runtime Environment, Java Technology Edition, Version 7 on most platforms by default. That version is used to run Java user-defined routines that are created in the server.

You can upgrade a high-availability cluster to the next fix pack or interim update (PID) with minimal interruption to client applications. During the rolling upgrade process, the cluster remains online even though the servers in the cluster are running on different levels of the software.

For example, to upgrade from 12.10.xC4 to 12.10.xC5: Stop a secondary server in the cluster, install the new fix pack on it, and then start the upgraded server. After you upgrade all of the secondary servers, stop the primary server and promote one of the secondary servers to the primary server. Then, you can upgrade the original primary server, start it as a secondary server, and then promote it back to primary server.

Due to new features and functionality, Informix 12.10.xC4 contains the following server changes:

• New configuration parameters: CDR_MEM, SESSION_LIMIT_LOCKS
• Changed configuration parameter: VP_MEMORY_CACHE_KB
• New environment variable: IFX_PUA_DISPLAY_MAPPING
• New session environment option: IFX_SESSION_LIMIT_LOCKS
• New SQL reserved word: IFX_SESSION_LIMIT_LOCKS
• New system database table: tenant
• Changed sysindices system catalog table: Contains new columns, indexattr and jparam

The details are described in the HCL Informix Administrator's Reference and the IBM Informix Guide to SQL: Reference.

Environment variable changes by version

SQL keyword changes by version

System catalog and system database changes by version

Due to new functionality, if you use Enterprise Replication you must run conversion (concdr.extension ) and reversion (revcdr.extension) scripts to migrate between Informix 12.10 fix packs.

Reverting with Enterprise Replication

Support for JSON in databases was introduced in the 12.10.xC2 release, and databases created in 12.10.xC1 or earlier releases are not JSON compatible.

Before you migrate to 12.10.xC4: No special preparation is necessary. The only exception is if you are migrating from 12.10.xC2 and you have binary JSON (BSON) columns with DATE fields. In that case you must unload the data by using an external table so that you can load the data into a new database table after migration.

After you migrate to 12.10.xC4: All databases are converted to support JSON. If you migrated from 12.10.xC2 or 12.10.xC3, you might have to complete some post-migration steps depending on what JSON features you had used.

If you revert to 12.10.xC2 or 12.10.xC3: Any databases that did not support JSON before conversion do not support JSON after reversion. However, you can run a script to make such databases JSON compatible.

Completing required post-migration tasks

Add JSON compatibility to databases that were created in 12.10.xC1

You can allocate space efficiently when you import tables that have large rows by setting a default extent size of 16 KB. Include the new -D option of the dbimport utility to specify a default extent size of 16 KB. Extent sizes that you specify in the CREATE TABLE statement override the -D option. The -D option is useful especially when you import huge tables that contain large LVARCHAR columns.

Removing outstanding in-place alter operations improves performance and is a prerequisite for reverting to an earlier version of Informix. You can easily remove outstanding in-place alter operations for tables or fragments in HCL OpenAdmin Tool (OAT) for Informix or with the new table update_ipa or fragment update_ipa argument of the admin() or task() SQL administration command. Previously, you ran a dummy UPDATE statement to remove outstanding in-place alter operations.

Informix 12.10.xC3 includes new or changed configuration parameters, environment variables, and system catalog tables.

Environment variable changes by version

Before you migrate from Informix 12.10.xC2, if you have binary JSON (BSON) columns with DATE fields you must unload the data from the database server in JSON format by using an external table. After you migrate to 12.10.xC3, you must load the data from the external table into a new database server table in BSON format.

If your databases were created in earlier versions of Informix 12.10, you must complete some post-migration steps for JSON compatibility:

• Run the convTovNoSQL1210.sql script on databases that were originally created in 12.10.xC1 to make them JSON compatible.
• If you used the JSON wire listener in 12.10.xC2 with a database that has any uppercase letters in its name, update your applications to use only lowercase letters in the database name.

Completing required post-migration tasks

After you migrate to 12.10.xC3, you can revert to the version of the database server from which you migrated if the reversion requirements are met.

You can significantly increase the speed of loading or migrating large tables by temporarily preventing the database server from validating foreign-key referential constraints. You can disable the validation of constraints when you create constraints or change the mode of constraints to ENABLED or FILTERING.

When you migrate data, include the -nv option in the dbimport command.

Use this feature only on tables whose enabled foreign-key constraints are free of violations, or when the referential constraints can be validated after the tables are loaded or migrated to the target database.

Informix 12.10.xC2 includes new and changed configuration parameters and environment variables. This fix pack also supports these new SQL keywords: BSON, JSON, LATERAL.

Before you can use JSON features with databases that were created in 12.10.xC1, you must run the convTovNoSQL1210X2.sql script after you install 12.10.xC2. However, if the databases do not require JSON compatibility, you do not have to run this script.

After you migrate to Informix 12.10.xC2, you can revert to the version of the database server from which you migrated as long as the reversion requirements are met.

If you are migrating from Informix Version 11.70, 11.50, 11.10, or 10.0, you can migrate directly to Informix Version 12.10.

If you have a 64-bit ODBC application that was compiled and linked with a version of HCL Informix Client Software Development Kit (Client SDK) that is prior to version 4.10, you must recompile the application after migrating.