CREATE_OPERATOR_CLASS(7pg15)

📦 version 15.19, in opensuse-leap 16.0

💅 CREATE OPERATOR CLASS(7) 💅

okay bestie, so we're doing CREATE OPERATOR CLASS today — it's from the PostgreSQL 15.19 Documentation and honestly it's giving "define a whole new operator class" main character energy. let me walk you through it 🫶

✨ NAME ✨

CREATE_OPERATOR_CLASS — define a new operator class. that's it, that's the vibe 🌸

🎀 SYNOPSIS 🎀

CREATE OPERATOR CLASS name [ DEFAULT ] FOR TYPE data_type
  USING index_method [ FAMILY family_name ] AS
  {  OPERATOR strategy_number operator_name [ ( op_type, op_type ) ] [ FOR SEARCH | FOR ORDER BY sort_family_name ]
   | FUNCTION support_number [ ( op_type [ , op_type ] ) ] function_name ( argument_type [, ...] )
   | STORAGE storage_type
  } [, ... ]

copy it exactly like that, no cap 💅

🦋 DESCRIPTION 🦋

CREATE OPERATOR CLASS creates a new operator class, periodt. and like... what is an operator class? bestie it's the whole blueprint for how a particular data type can be used with an index. it literally specifies that certain operators will fill particular roles — the docs call them “strategies” — for this data type and this index method. it also specifies the support functions that the index method is gonna use when the operator class gets selected for an index column. iconic.

⚠️ heads up: all the operators and functions used by an operator class must already be defined before you can create the operator class. no creating stuff out of thin air, bestie.

if you give a schema name then the operator class is created in that specified schema. otherwise it's created in the current schema. two operator classes in the same schema can have the same name only if they're for different index methods — otherwise it's a vibe check fail 💀

the user who defines an operator class becomes its owner. presently, the creating user must be a superuser. (and the reason for that restriction is lowkey serious — an erroneous operator class definition could confuse or even crash the server 😭)

and ngl, CREATE OPERATOR CLASS does not presently check whether the operator class definition includes all the operators and functions required by the index method, nor whether the operators and functions form a self-consistent set. it is the user's responsibility to define a valid operator class. you're the main character, you handle it 👑

related operator classes can be grouped into operator families. to add a new operator class to an existing family, specify the FAMILY option in CREATE OPERATOR CLASS. without this option, the new class is placed into a family named the same as the new class (creating that family if it doesn't already exist). cute, right? 🎀

refer to Section 38.16 for further information.

💖 PARAMETERS 💖

  • name — the name of the operator class to be created. the name can be schema-qualified. slay ✨
  • DEFAULT — if present, the operator class will become the default operator class for its data type. at most one operator class can be the default for a specific data type and index method. one (1) default only, bestie, we don't do drama here 🙈
  • data_type — the column data type that this operator class is for. that's the whole point, iykyk.
  • index_method — the name of the index method this operator class is for. like gist, btree, etc. 💅
  • family_name — the name of the existing operator family to add this operator class to. if not specified, a family named the same as the operator class is used (creating it, if it doesn't already exist). it's giving "found family" honestly 🫶
  • strategy_number — the index method's strategy number for an operator associated with the operator class. the number matters, don't freestyle it.
  • operator_name — the name (optionally schema-qualified) of an operator associated with the operator class.
  • op_type — okay this one has two whole moods, so listen up:
    • in an OPERATOR clause, it's the operand data type(s) of the operator, or NONE to signify a prefix operator. the operand data types can be omitted in the normal case where they're the same as the operator class's data type.
    • in a FUNCTION clause, it's the operand data type(s) the function is intended to support, if different from the input data type(s) of the function (for B-tree comparison functions and hash functions) or the class's data type (for B-tree sort support functions, B-tree equal image functions, and all functions in GiST, SP-GiST, GIN and BRIN operator classes).
    • these defaults are correct, and so op_type need not be specified in FUNCTION clauses, except for the case of a B-tree sort support function that is meant to support cross-data-type comparisons. literally the one exception, bestie 📌
  • sort_family_name — the name (optionally schema-qualified) of an existing btree operator family that describes the sort ordering associated with an ordering operator.
if neither FOR SEARCH nor FOR ORDER BY is specified, FOR SEARCH is the default. default behavior, love that for you ✨
  • support_number — the index method's support function number for a function associated with the operator class.
  • function_name — the name (optionally schema-qualified) of a function that is an index method support function for the operator class.
  • argument_type — the parameter data type(s) of the function.
  • storage_type — the data type actually stored in the index. normally this is the same as the column data type, but some index methods (currently GiST, GIN, SP-GiST and BRIN) allow it to be different. the STORAGE clause must be omitted unless the index method allows a different type to be used. if the column data_type is specified as anyarray, the storage_type can be declared as anyelement to indicate that the index entries are members of the element type belonging to the actual array type that each particular index is created for. fancy 🌈

the OPERATOR, FUNCTION, and STORAGE clauses can appear in any order — go off, structure it however you want, no rules (okay some rules, but not that one) 🦋

💀 NOTES 💀

because the index machinery does not check access permissions on functions before using them, including a function or operator in an operator class is tantamount to granting public execute permission on it. 😳 usually this is not an issue for the sorts of functions that are useful in an operator class, but like... know that you're doing that, bestie.

the operators should not be defined by SQL functions. an SQL function is likely to be inlined into the calling query, which will prevent the optimizer from recognizing that the query matches an index. that's a whole tragedy, don't do it 🙈

before PostgreSQL 8.4, the OPERATOR clause could include a RECHECK option. this is no longer supported because whether an index operator is “lossy” is now determined on-the-fly at run time. this allows efficient handling of cases where an operator might or might not be lossy. rip RECHECK, you had a good run 💐

🔥 EXAMPLES 🔥

the following example command defines a GiST index operator class for the data type _int4 (array of int4). see the intarray module for the complete example. this one ate, ngl 👑

CREATE OPERATOR CLASS gist__int_ops
    DEFAULT FOR TYPE _int4 USING gist AS
        OPERATOR        3       &&,
        OPERATOR        6       = (anyarray, anyarray),
        OPERATOR        7       @>,
        OPERATOR        8       <@,
        OPERATOR        20      @@ (_int4, query_int),
        FUNCTION        1       g_int_consistent (internal, _int4, smallint, oid, internal),
        FUNCTION        2       g_int_union (internal, internal),
        FUNCTION        3       g_int_compress (internal),
        FUNCTION        4       g_int_decompress (internal),
        FUNCTION        5       g_int_penalty (internal, internal, internal),
        FUNCTION        6       g_int_picksplit (internal, internal),
        FUNCTION        7       g_int_same (_int4, _int4, internal);

🌈 COMPATIBILITY 🌈

CREATE OPERATOR CLASS is a PostgreSQL extension. there is no CREATE OPERATOR CLASS statement in the SQL standard. we're built different, fr fr ⭐

🧚 SEE ALSO 🧚

go read those next, bestie, they're all linked up 🫶

and that's the whole page!! 🌸 this little love letter came to you from PostgreSQL 15.19, dated 2026, and it will forever be titled CREATE OPERATOR CLASS(7). mwah 💋 slay, bye!! 🎀
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