pg_type

字段

PostgreSQL 18 的 32 个字段，按定义顺序排列。说明默认用本站手册的译文，没有译文的按英文原文显示。

演化历史

相邻两个大版本之间的差异，新的在前。版本号链到该版的字段表。

1. PostgreSQL 19 ← 18 仅描述更新

   2 处描述更新

   • typacl Access privileges; see Section 5.8 for details Access privileges; see Section 5.9 for details
   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 52.65. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 52.70.

2. PostgreSQL 18 ← 17 仅描述更新

   1 处描述更新

   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 51.65. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 52.65.

3. PostgreSQL 17 ← 16 仅描述更新

   2 处描述更新

   • typacl Access privileges; see Section 5.7 for details Access privileges; see Section 5.8 for details
   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 53.65. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 51.65.

4. PostgreSQL 15 ← 14 仅描述更新

   1 处描述更新

   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 52.63. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 53.65.

5. PostgreSQL 14 ← 13 结构变更

   +typsubscript

   9 处描述更新

   • typanalyze Custom ANALYZE function, or 0 to use the standard function Custom ANALYZE function, or zero to use the standard function
   • typarray If typarray is not 0 then it identifies another row in pg_type, which is the “true” array type having this type as element If typarray is not zero then it identifies another row in pg_type, which is the “true” array type having this type as element
   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 51.63. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 52.63.
   • typelem If typelem is not 0 then it identifies another row in pg_type. The current type can then be subscripted like an array yielding values of type typelem. A “true” array type is variable length (typlen = -1), but some fixed-length (typlen > 0) types also have nonzero typelem, for example name and point. If a fixed-length type has a typelem then its internal representation must be some number of values of the typelem data type with no other data. Variable-length array types have a header defined by the array subroutines. If typelem is not zero then it identifies another row in pg_type, defining the type yielded by subscripting. This should be zero if typsubscript is zero. However, it can be zero when typsubscript isn't zero, if the handler doesn't need typelem to determine the subscripting result type. Note that a typelem dependency is considered to imply physical containment of the element type in this type; so DDL changes on the element type might be restricted by the presence of this type.
   • typmodin Type modifier input function, or 0 if type does not support modifiers Type modifier input function, or zero if type does not support modifiers
   • typmodout Type modifier output function, or 0 to use the standard format Type modifier output function, or zero to use the standard format
   • typreceive Input conversion function (binary format), or 0 if none Input conversion function (binary format), or zero if none
   • typsend Output conversion function (binary format), or 0 if none Output conversion function (binary format), or zero if none
   • typtype typtype is b for a base type, c for a composite type (e.g., a table's row type), d for a domain, e for an enum type, p for a pseudo-type, or r for a range type. See also typrelid and typbasetype. typtype is b for a base type, c for a composite type (e.g., a table's row type), d for a domain, e for an enum type, p for a pseudo-type, r for a range type, or m for a multirange type. See also typrelid and typbasetype.

6. PostgreSQL 13 ← 12 仅描述更新

   3 处描述更新

   • typalign typalign is the alignment required when storing a value of this type. It applies to storage on disk as well as most representations of the value inside PostgreSQL. When multiple values are stored consecutively, such as in the representation of a complete row on disk, padding is inserted before a datum of this type so that it begins on the specified boundary. The alignment reference is the beginning of the first datum in the sequence. Possible values are: c = char alignment, i.e., no alignment needed. s = short alignment (2 bytes on most machines). i = int alignment (4 bytes on most machines). d = double alignment (8 bytes on many machines, but by no means all). Note For types used in system tables, it is critical that the size and alignment defined in pg_type agree with the way that the compiler will lay out the column in a structure representing a table row. typalign is the alignment required when storing a value of this type. It applies to storage on disk as well as most representations of the value inside PostgreSQL. When multiple values are stored consecutively, such as in the representation of a complete row on disk, padding is inserted before a datum of this type so that it begins on the specified boundary. The alignment reference is the beginning of the first datum in the sequence. Possible values are:
   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 51.64. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 51.63.
   • typstorage typstorage tells for varlena types (those with typlen = -1) if the type is prepared for toasting and what the default strategy for attributes of this type should be. Possible values are p: Value must always be stored plain. e: Value can be stored in a “secondary” relation (if relation has one, see pg_class.reltoastrelid). m: Value can be stored compressed inline. x: Value can be stored compressed inline or stored in “secondary” storage. Note that m columns can also be moved out to secondary storage, but only as a last resort (e and x columns are moved first). typstorage tells for varlena types (those with typlen = -1) if the type is prepared for toasting and what the default strategy for attributes of this type should be. Possible values are: x is the usual choice for toast-able types. Note that m values can also be moved out to secondary storage, but only as a last resort (e and x values are moved first).

7. PostgreSQL 12 ← 11 结构变更

   oid：隐式列 → 常规列

   4 处描述更新

   • oid Row identifier (hidden attribute; must be explicitly selected) Row identifier
   • typacl Access privileges; see GRANT and REVOKE for details Access privileges; see Section 5.7 for details
   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 52.63. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 51.64.
   • typcollation typcollation specifies the collation of the type. If the type does not support collations, this will be zero. A base type that supports collations will have DEFAULT_COLLATION_OID here. A domain over a collatable type can have some other collation OID, if one was specified for the domain. typcollation specifies the collation of the type. If the type does not support collations, this will be zero. A base type that supports collations will have a nonzero value here, typically DEFAULT_COLLATION_OID. A domain over a collatable type can have a collation OID different from its base type's, if one was specified for the domain.

8. PostgreSQL 11 ← 10 仅描述更新

   1 处描述更新

   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 51.63. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 52.63.

9. PostgreSQL 10 ← 9.6 仅描述更新

   6 处描述更新

   • typalign typalign is the alignment required when storing a value of this type. It applies to storage on disk as well as most representations of the value inside PostgreSQL. When multiple values are stored consecutively, such as in the representation of a complete row on disk, padding is inserted before a datum of this type so that it begins on the specified boundary. The alignment reference is the beginning of the first datum in the sequence. Possible values are: c = char alignment, i.e., no alignment needed. s = short alignment (2 bytes on most machines). i = int alignment (4 bytes on most machines). d = double alignment (8 bytes on many machines, but by no means all). Note: For types used in system tables, it is critical that the size and alignment defined in pg_type agree with the way that the compiler will lay out the column in a structure representing a table row. typalign is the alignment required when storing a value of this type. It applies to storage on disk as well as most representations of the value inside PostgreSQL. When multiple values are stored consecutively, such as in the representation of a complete row on disk, padding is inserted before a datum of this type so that it begins on the specified boundary. The alignment reference is the beginning of the first datum in the sequence. Possible values are: c = char alignment, i.e., no alignment needed. s = short alignment (2 bytes on most machines). i = int alignment (4 bytes on most machines). d = double alignment (8 bytes on many machines, but by no means all). Note For types used in system tables, it is critical that the size and alignment defined in pg_type agree with the way that the compiler will lay out the column in a structure representing a table row.
   • typarray If typarray is not 0 then it identifies another row in pg_type, which is the "true" array type having this type as element If typarray is not 0 then it identifies another row in pg_type, which is the “true” array type having this type as element
   • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 50-56. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be “preferred”. See Table 51.63.
   • typelem If typelem is not 0 then it identifies another row in pg_type. The current type can then be subscripted like an array yielding values of type typelem. A "true" array type is variable length (typlen = -1), but some fixed-length (typlen > 0) types also have nonzero typelem, for example name and point. If a fixed-length type has a typelem then its internal representation must be some number of values of the typelem data type with no other data. Variable-length array types have a header defined by the array subroutines. If typelem is not 0 then it identifies another row in pg_type. The current type can then be subscripted like an array yielding values of type typelem. A “true” array type is variable length (typlen = -1), but some fixed-length (typlen > 0) types also have nonzero typelem, for example name and point. If a fixed-length type has a typelem then its internal representation must be some number of values of the typelem data type with no other data. Variable-length array types have a header defined by the array subroutines.
   • typlen For a fixed-size type, typlen is the number of bytes in the internal representation of the type. But for a variable-length type, typlen is negative. -1 indicates a "varlena" type (one that has a length word), -2 indicates a null-terminated C string. For a fixed-size type, typlen is the number of bytes in the internal representation of the type. But for a variable-length type, typlen is negative. -1 indicates a “varlena” type (one that has a length word), -2 indicates a null-terminated C string.
   • typstorage typstorage tells for varlena types (those with typlen = -1) if the type is prepared for toasting and what the default strategy for attributes of this type should be. Possible values are p: Value must always be stored plain. e: Value can be stored in a "secondary" relation (if relation has one, see pg_class.reltoastrelid). m: Value can be stored compressed inline. x: Value can be stored compressed inline or stored in "secondary" storage. Note that m columns can also be moved out to secondary storage, but only as a last resort (e and x columns are moved first). typstorage tells for varlena types (those with typlen = -1) if the type is prepared for toasting and what the default strategy for attributes of this type should be. Possible values are p: Value must always be stored plain. e: Value can be stored in a “secondary” relation (if relation has one, see pg_class.reltoastrelid). m: Value can be stored compressed inline. x: Value can be stored compressed inline or stored in “secondary” storage. Note that m columns can also be moved out to secondary storage, but only as a last resort (e and x columns are moved first).

10. PostgreSQL 9.6 ← 9.5 仅描述更新

    1 处描述更新

    • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 49-55. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 50-56.

11. PostgreSQL 9.5 ← 9.4 仅描述更新

    1 处描述更新

    • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 48-53. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 49-55.

12. PostgreSQL 9.4 ← 9.3 仅描述更新

    1 处描述更新

    • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 47-52. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 48-53.

13. PostgreSQL 9.3 ← 9.2 仅描述更新

    2 处描述更新

    • oid Row identifier (hidden system attribute; explicitly select oid). Row identifier (hidden attribute; must be explicitly selected)
    • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 45-51. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 47-52.

14. PostgreSQL 9.2 ← 9.1 结构变更

    +typacl

    2 处描述更新

    • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 45-49. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 45-51.
    • typtype typtype is b for a base type, c for a composite type (e.g., a table's row type), d for a domain, e for an enum type, or p for a pseudo-type. See also typrelid and typbasetype. typtype is b for a base type, c for a composite type (e.g., a table's row type), d for a domain, e for an enum type, p for a pseudo-type, or r for a range type. See also typrelid and typbasetype.

15. PostgreSQL 9.1 ← 9.0 结构变更

    +typcollation typdefaultbin：text → pg_node_tree

    3 处描述更新

    • typcategory typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 45-45. typcategory is an arbitrary classification of data types that is used by the parser to determine which implicit casts should be "preferred". See Table 45-49.
    • typdefault typdefault is null if the type has no associated default value. If typdefaultbin is not null, typdefault must contain a human-readable version of the default expression represented by typdefaultbin. If typdefaultbin is null and typdefault is not, then typdefault is the external representation of the type's default value, which might be fed to the type's input converter to produce a constant. typdefault is null if the type has no associated default value. If typdefaultbin is not null, typdefault must contain a human-readable version of the default expression represented by typdefaultbin. If typdefaultbin is null and typdefault is not, then typdefault is the external representation of the type's default value, which can be fed to the type's input converter to produce a constant.
    • typndims typndims is the number of array dimensions for a domain that is an array (that is, typbasetype is an array type; the domain's typelem will match the base type's typelem). Zero for types other than domains over array types. typndims is the number of array dimensions for a domain over an array (that is, typbasetype is an array type). Zero for types other than domains over array types.

字段矩阵

每个字段在 18 个收录版本里的存在情况；方格指向该版的字段表。「有变」指类型、可空、隐式或数组维数与上一版不同。

存在 有变 已移除 不存在

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