SYSTEM CATALOG · System catalog

pg_amop

PostgreSQL documentation ↗Source definition ↗

The catalog pg_amop stores information about operators associated with access method operator families. There is one row for each operator that is a member of an operator family. A family member can be either a search operator or an ordering operator. An operator can appear in more than one family, but cannot appear in more than one search position nor more than one ordering position within a family. (It is allowed, though unlikely, for an operator to be used for both search and ordering purposes.)

First seen PG 9.0Last seen PG 19Columns 9

9.0 9.1 9.2 9.3 9.4 9.5 9.6 10 11 12 13 14 15 16 17 18 19^β3

Checked column by column against a PostgreSQL 18.6 instance · Raw measurement record ↗

Columns PostgreSQL 18

pg_amop

COLUMN	TYPE	DESCRIPTION
`oid`	`oid`NOT NULL	Row identifier
`amopfamily`	`oid`NOT NULL	The operator family this entry is forReferences:`pg_opfamily.oid`
`amoplefttype`	`oid`NOT NULL	Left-hand input data type of operatorReferences:`pg_type.oid`
`amoprighttype`	`oid`NOT NULL	Right-hand input data type of operatorReferences:`pg_type.oid`
`amopstrategy`	`smallint`NOT NULLDocumented as:`int2`	Operator strategy number
`amoppurpose`	`"char"`NOT NULLDocumented as:`char`	Operator purpose, either s for search or o for ordering
`amopopr`	`oid`NOT NULL	OID of the operatorReferences:`pg_operator.oid`
`amopmethod`	`oid`NOT NULL	Index access method operator family is forReferences:`pg_am.oid`
`amopsortfamily`	`oid`NOT NULL	The B-tree operator family this entry sorts according to, if an ordering operator; zero if a search operatorReferences:`pg_opfamily.oid`

Columns marked "implicit" are not included in SELECT *; some early statistics views are completed from same-version source, and the extra provenance is shown in the column description.

Common system columns 6

System attributes PostgreSQL provides, normally not expanded by SELECT *. Kept separately so they are not mixed in with ordinary columns.

Columns	Type	attnum
`tableoid`	`oid`	-6
`cmax`	`cid`	-5
`xmax`	`xid`	-4
`cmin`	`cid`	-3
`xmin`	`xid`	-2
`ctid`	`tid`	-1

Column evolution matrix

Hover a cell for the column type

PresentAdded / type or attribute changeRemoved

COLUMN	9.0	9.1	9.2	9.3	9.4	9.5	9.6	10	11	12	13	14	15	16	17	18	19
`oid`
`amopfamily`
`amoplefttype`
`amoprighttype`
`amopstrategy`
`amopopr`
`amopmethod`
`amoppurpose`	–
`amopsortfamily`	–

9.0 is the coverage baseline; a column already present in the baseline is not marked as added. The matrix aligns columns by name, so a rename appears as the old column removed and a new column added.

Evolution timeline

Changes between adjacent majors

PostgreSQL 12 ← 11

~ oid: implicit → ordinary1 column description updates

PostgreSQL 9.4 ← 9.3

1 column description updates

PostgreSQL 9.3 ← 9.2

1 column description updates

PostgreSQL 9.1 ← 9.0

+ amoppurpose+ amopsortfamilyCatalog description updated

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