48.15. pg_am
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48.15. pg_am

The catalog pg_am stores information about relation access methods. There is one row for each access method supported by the system. Currently, only tables and indexes have access methods. The requirements for table and index access methods are discussed in detail in Chapter 56 and Chapter 57 respectively.

Table 48.15. pg_am Columns

Column Type

Description

oid oid

Row identifier

amname name

Name of the access method

amhandler regproc (references pg_proc.oid)

OID of a handler function that is responsible for supplying information about the access method

amtype char

t = table, i = index.


Note

Before LightDB 9.6, pg_am contained many additional columns representing properties of index access methods. That data is now only directly visible at the C code level. However, pg_index_column_has_property() and related functions have been added to allow SQL queries to inspect index access method properties; see Table 10.66.

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48.14. pg_aggregate Home 48.16. pg_amop