如何在PostgreSQL中获取表的列列名和数据类型？

Question

通过以下查询，我们可以获得PostgreSQL中表的列名和数据类型列表。

Answer 1

打开psql commande行并输入：

\d+ table_name

Answer 2

select column_name,data_type 
from information_schema.columns 
where table_name = 'table_name';

使用上面的查询，您可以使用列及其数据类型

Answer 3

SELECT
        a.attname as "Column",
        pg_catalog.format_type(a.atttypid, a.atttypmod) as "Datatype"
    FROM
        pg_catalog.pg_attribute a
    WHERE
        a.attnum > 0
        AND NOT a.attisdropped
        AND a.attrelid = (
            SELECT c.oid
            FROM pg_catalog.pg_class c
                LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
            WHERE c.relname ~ '^(hello world)$'
                AND pg_catalog.pg_table_is_visible(c.oid)
        );

有关详情：http://www.postgresql.org/docs/9.3/static/catalog-pg-attribute.html

Answer 4

如果您有多个具有相同表名的架构，请不要忘记添加架构名称。

SELECT column_name, data_type 
FROM information_schema.columns
WHERE table_name = 'your_table_name' AND table_schema = 'your_schema_name';

或使用psql：

\d+ your_schema_name.your_table_name

Answer 5

更新的Pratik答案以支持更多模式和可为空值

SELECT
    "pg_attribute".attname                                                    as "Column",
    pg_catalog.format_type("pg_attribute".atttypid, "pg_attribute".atttypmod) as "Datatype",

    not("pg_attribute".attnotnull) AS "Nullable"
FROM
    pg_catalog.pg_attribute "pg_attribute"
WHERE
    "pg_attribute".attnum > 0
    AND NOT "pg_attribute".attisdropped
    AND "pg_attribute".attrelid = (
        SELECT "pg_class".oid
        FROM pg_catalog.pg_class "pg_class"
            LEFT JOIN pg_catalog.pg_namespace "pg_namespace" ON "pg_namespace".oid = "pg_class".relnamespace
        WHERE
            "pg_namespace".nspname = 'schema'
            AND "pg_class".relname = 'table'
    );

Answer 6

如果不提及架构，您也可以获得所需的详细信息 试试这个查询->

选择列名，数据类型 来自information_schema.columns 其中table_name ='table_name';

Answer 7

要获取有关表列的信息，可以使用：

\dt+ [tablename]

要获取有关表中数据类型的信息，可以使用：

\dT+ [datatype]

Answer 8

    SELECT DISTINCT
        ROW_NUMBER () OVER (ORDER BY pgc.relname , a.attnum) as rowid , 
        pgc.relname as table_name ,
        a.attnum as attr,
        a.attname as name,
        format_type(a.atttypid, a.atttypmod) as typ,
        a.attnotnull as notnull, 
        com.description as comment,
        coalesce(i.indisprimary,false) as primary_key,
        def.adsrc as default
    FROM pg_attribute a 
    JOIN pg_class pgc ON pgc.oid = a.attrelid
    LEFT JOIN pg_index i ON 
        (pgc.oid = i.indrelid AND i.indkey[0] = a.attnum)
    LEFT JOIN pg_description com on 
        (pgc.oid = com.objoid AND a.attnum = com.objsubid)
    LEFT JOIN pg_attrdef def ON 
        (a.attrelid = def.adrelid AND a.attnum = def.adnum)
    LEFT JOIN pg_catalog.pg_namespace n ON n.oid = pgc.relnamespace

    WHERE 1=1 
        AND pgc.relkind IN ('r','')
        AND n.nspname <> 'pg_catalog'
        AND n.nspname <> 'information_schema'
        AND n.nspname !~ '^pg_toast'

    AND a.attnum > 0 AND pgc.oid = a.attrelid
    AND pg_table_is_visible(pgc.oid)
    AND NOT a.attisdropped
    ORDER BY rowid
    ;

Answer 9

从information_schema.columns中选择column_name，data_type，其中 table_name ='your_table_name'和table_catalog ='your_database_name'和table_schema ='your_schema_name';

Answer 10

使该主题“更完整”。

我需要SELECT语句（不是表）上的列名和数据类型。

如果要在SELECT语句而不是实际的现有表上执行此操作，则可以执行以下操作：

DROP TABLE IF EXISTS abc;
CREATE TEMPORARY TABLE abc AS
-- your select statement here!
SELECT 
    *
FROM foo
-- end your select statement
;

select column_name, data_type 
from information_schema.columns 
where table_name = 'abc';
DROP IF EXISTS abc;

简短的解释是，它为您的select语句创建了一个（临时）表，您可以通过@a_horse_with_no_name和@selva提供的查询来“调用”该表。

希望这会有所帮助。

Answer 11

该版本支持在特定架构中查找表的列名和类型，并使用JOIN而不包含任何子查询

SELECT
    pg_attribute.attname AS column_name,
    pg_catalog.format_type(pg_attribute.atttypid, pg_attribute.atttypmod) AS data_type
FROM
    pg_catalog.pg_attribute
INNER JOIN
    pg_catalog.pg_class ON pg_class.oid = pg_attribute.attrelid
INNER JOIN
    pg_catalog.pg_namespace ON pg_namespace.oid = pg_class.relnamespace
WHERE
    pg_attribute.attnum > 0
    AND NOT pg_attribute.attisdropped
    AND pg_namespace.nspname = 'my_schema'
    AND pg_class.relname = 'my_table'
ORDER BY
    attnum ASC;

Answer 12

下面将列出所提供模式名称中所有表的所有不同数据类型。

\copy (select distinct data_type, column_name from information_schema.columns where table_name in (SELECT tablename FROM pg_catalog.pg_tables WHERE schemaname != 'pg_catalog' AND schemaname != 'information_schema' and schemaname = '<Your schema name>')) to 'datatypes.csv'  delimiter as ',' CSV header