The pageinspect module provides functions for low level inspection of the contents of database pages. pageinspect is available only to Greenplum Database superusers.

The Greenplum Database pageinspect module is based on the PostgreSQL pageinspect module. The Greenplum version of the module differs only in that it does not allow inspection of pages belonging to append-optimized or external relations.

Installing and Registering the Module

The pageinspect module is installed when you install Greenplum Database. Before you can use any of the functions defined in the module, you must register the pageinspect extension in each database in which you want to use the functions. Refer to Installing Additional Supplied Modules for more information.

Module Documentation

See pageinspect in the PostgreSQL documentation for detailed information about the individual functions in this module.

Note: For pageinspect functions that read data from a database, the function reads data only from the segment instance where the function is run. For example, the get_raw_page() function returns a block number out of range error when you try to read data from a user-defined table on the Greenplum Database master because there is no data in the table on the master segment. The function will read data from a system catalog table on the master segment.