DB2 Version 10.1 for Linux, UNIX, and Windows

sqlarbnd API - Rebind package

Allows the user to re-create a package stored in the database without the need for a bind file.

Authorization

One of the following authorities:
  • DBADM authority
  • ALTERIN privilege on the schema
  • BIND privilege on the package.

The authorization ID logged in the BOUNDBY column of the SYSCAT.PACKAGES system catalog table, which is the ID of the most recent binder of the package, is used as the binder authorization ID for the rebind, and for the default schema for table references in the package. Note that this default qualifier may be different from the authorization ID of the user executing the rebind request. REBIND will use the same bind options that were specified when the package was created.

Required connection

Database

API include file

sql.h

API and data structure syntax

SQL_API_RC SQL_API_FN
  sqlarbnd (
        char * pPackageName,
        struct sqlca * pSqlca,
        struct sqlopt * pRebindOptions);

SQL_API_RC SQL_API_FN
  sqlgrbnd (
        unsigned short PackageNameLen,
        char * pPackageName,
        struct sqlca * pSqlca,
        struct sqlopt * pRebindOptions);

sqlarbnd API parameters

pPackageName
Input. A string containing the qualified or unqualified name that designates the package to be rebound. An unqualified package-name is implicitly qualified by the current authorization ID. This name does not include the package version. When specifying a package that has a version that is not the empty string, then the version-id must be specified using the SQL_VERSION_OPT rebind option.
pSqlca
Output. A pointer to the sqlca structure.
pRebindOptions
Input. A pointer to the SQLOPT structure, used to pass rebind options to the API. For more information about this structure, see SQLOPT.

sqlgrbnd API-specific parameters

PackageNameLen
Input. Length in bytes of the pPackageName parameter.

Usage notes

REBIND does not automatically commit the transaction following a successful rebind. The user must explicitly commit the transaction. This enables "what if " analysis, in which the user updates certain statistics, and then tries to rebind the package to see what changes. It also permits multiple rebinds within a unit of work.

This API:
  • Provides a quick way to re-create a package. This enables the user to take advantage of a change in the system without a need for the original bind file. For example, if it is likely that a particular SQL statement can take advantage of a newly created index, REBIND can be used to re-create the package. REBIND can also be used to re-create packages after db2Runstats has been executed, thereby taking advantage of the new statistics.
  • Provides a method to re-create inoperative packages. Inoperative packages must be explicitly rebound by invoking either the bind utility or the rebind utility. A package will be marked inoperative (the VALID column of the SYSCAT.PACKAGES system catalog will be set to X) if a function instance on which the package depends is dropped. The rebind conservative option is not supported for inoperative packages.
  • Gives users control over the rebinding of invalid packages. Invalid packages will be automatically (or implicitly) rebound by the database manager when they are executed. This may result in a noticeable delay in the execution of the first SQL request for the invalid package. It may be desirable to explicitly rebind invalid packages, rather than allow the system to automatically rebind them, in order to eliminate the initial delay and to prevent unexpected SQL error messages which may be returned in case the implicit rebind fails. For example, following database upgrade, all packages stored in the database will be invalidated by the UPGRADE DATABASE command. Given that this may involve a large number of packages, it may be desirable to explicitly rebind all of the invalid packages at one time. This explicit rebinding can be accomplished using BIND, REBIND, or the db2rbind tool.
The choice of whether to use BIND or REBIND to explicitly rebind a package depends on the circumstances. It is recommended that REBIND be used whenever the situation does not specifically require the use of BIND, since the performance of REBIND is significantly better than that of BIND. BIND must be used, however:
  • When there have been modifications to the program (for example, when SQL statements have been added or deleted, or when the package does not match the executable for the program).
  • When the user wishes to modify any of the bind options as part of the rebind. REBIND does not support any bind options. For example, if the user wishes to have privileges on the package granted as part of the bind process, BIND must be used, since it has an SQL_GRANT_OPT option.
  • When the package does not currently exist in the database.
  • When detection of all bind errors is desired. REBIND only returns the first error it detects, and then ends, whereas the BIND command returns the first 100 errors that occur during binding.

REBIND is supported by DB2 Connect™.

If REBIND is executed on a package that is in use by another user, the rebind will not occur until the other user's logical unit of work ends, because an exclusive lock is held on the package's record in the SYSCAT.PACKAGES system catalog table during the rebind.

When REBIND is executed, the database manager re-creates the package from the SQL statements stored in the SYSCAT.STATEMENTS system catalog table. If many versions with the same package number and creator exist, only one version can be bound at once. If not specified using the SQL_VERSION_OPT rebind option, the VERSION defaults to be "". Even if there is only one package with a name and creator that matches the name and creator specified in the rebind request, it will not rebound unless its VERSION matches the VERSION specified explicitly or implicitly.

If REBIND encounters an error, processing stops, and an error message is returned.

The Explain tables are populated during REBIND if either SQL_EXPLSNAP_OPT or SQL_EXPLAIN_OPT have been set to YES or ALL (check EXPLAIN_SNAPSHOT and EXPLAIN_MODE columns in the catalog). The Explain tables used are those of the REBIND requester, not the original binder. The Rebind option types and values are defined in sql.h.

REXX API syntax

This API can be called from REXX through the SQLDB2 interface.