Postgresql 中文操作指南

37.55. transforms #

视图 transforms 包含有关当前数据库中定义的转换的信息。更准确地说，它包含转换中包含的每个函数（“从 SQL”或“到 SQL”函数）的行。

The view transforms contains information about the transforms defined in the current database. More precisely, it contains a row for each function contained in a transform (the “from SQL” or “to SQL” function).

Table 37.53. transforms Columns

Column Type

Description

udt_catalog sql_identifier

Name of the database that contains the type the transform is for (always the current database)

udt_schema sql_identifier

Name of the schema that contains the type the transform is for

udt_name sql_identifier

Name of the type the transform is for

specific_catalog sql_identifier

Name of the database containing the function (always the current database)

specific_schema sql_identifier

Name of the schema containing the function

specific_name sql_identifier

The “specific name” of the function. See Section 37.45 for more information.

group_name sql_identifier

The SQL standard allows defining transforms in “groups”, and selecting a group at run time. PostgreSQL does not support this. Instead, transforms are specific to a language. As a compromise, this field contains the language the transform is for.

transform_type character_data

FROM SQL or TO SQL