如何使用psql命令在PostgreSQL中执行Oracle的DESCRIBE TABLE?


当前回答

/dt是列出数据库中所有表的命令。使用/d命令和/d+,我们可以获得表的详细信息。sysntax将如下所示*/d table_name(或)\d+table_name

其他回答

即使请求了psql命令,我也会添加pg_dump命令。因为它生成了以前的MySQl用户更常见的输出。

#sudo-u postgres pg_dump--table=my_table_name--仅模式mydb

为了改进另一个答案的SQL查询(这太棒了!),这里有一个经过修改的查询。它还包括约束名称、继承信息和数据类型,这些数据类型被划分为其组成部分(类型、长度、精度、比例)。它还过滤掉已删除的列(这些列仍然存在于数据库中)。

SELECT
    n.nspname as schema,
    c.relname as table,
    f.attname as column,  
    f.attnum as column_id,  
    f.attnotnull as not_null,
    f.attislocal not_inherited,
    f.attinhcount inheritance_count,
    pg_catalog.format_type(f.atttypid,f.atttypmod) AS data_type_full,
    t.typname AS data_type_name,
    CASE  
        WHEN f.atttypmod >= 0 AND t.typname <> 'numeric'THEN (f.atttypmod - 4) --first 4 bytes are for storing actual length of data
    END AS data_type_length, 
    CASE  
        WHEN t.typname = 'numeric' THEN (((f.atttypmod - 4) >> 16) & 65535)
    END AS numeric_precision,   
    CASE  
        WHEN t.typname = 'numeric' THEN ((f.atttypmod - 4)& 65535 )
    END AS numeric_scale,       
    CASE  
        WHEN p.contype = 'p' THEN 't'  
        ELSE 'f'  
    END AS is_primary_key,  
    CASE
        WHEN p.contype = 'p' THEN p.conname
    END AS primary_key_name,
    CASE  
        WHEN p.contype = 'u' THEN 't'  
        ELSE 'f'
    END AS is_unique_key,
    CASE
        WHEN p.contype = 'u' THEN p.conname
    END AS unique_key_name,
    CASE
        WHEN p.contype = 'f' THEN 't'
        ELSE 'f'
    END AS is_foreign_key,
    CASE
        WHEN p.contype = 'f' THEN p.conname
    END AS foreignkey_name,
    CASE
        WHEN p.contype = 'f' THEN p.confkey
    END AS foreign_key_columnid,
    CASE
        WHEN p.contype = 'f' THEN g.relname
    END AS foreign_key_table,
    CASE
        WHEN p.contype = 'f' THEN p.conkey
    END AS foreign_key_local_column_id,
    CASE
        WHEN f.atthasdef = 't' THEN d.adsrc
    END AS default_value
FROM pg_attribute f  
    JOIN pg_class c ON c.oid = f.attrelid  
    JOIN pg_type t ON t.oid = f.atttypid  
    LEFT JOIN pg_attrdef d ON d.adrelid = c.oid AND d.adnum = f.attnum  
    LEFT JOIN pg_namespace n ON n.oid = c.relnamespace  
    LEFT JOIN pg_constraint p ON p.conrelid = c.oid AND f.attnum = ANY (p.conkey)  
    LEFT JOIN pg_class AS g ON p.confrelid = g.oid  
WHERE c.relkind = 'r'::char  
    AND f.attisdropped = false
    AND n.nspname = '%s'  -- Replace with Schema name  
    AND c.relname = '%s'  -- Replace with table name  
    AND f.attnum > 0 
ORDER BY f.attnum
;

您可以使用此选项:

SELECT attname 
FROM pg_attribute,pg_class 
WHERE attrelid=pg_class.oid 
AND relname='TableName' 
AND attstattarget <>0; 

尝试以下操作(在psql命令行工具中):

\d+ tablename

有关更多信息,请参阅手册。

我为get表模式编写了以下脚本。

'CREATE TABLE ' || 'yourschema.yourtable' || E'\n(\n' ||
array_to_string(
array_agg(
'    ' || column_expr
)
, E',\n'
) || E'\n);\n'
from
(
SELECT '    ' || column_name || ' ' || data_type || 
coalesce('(' || character_maximum_length || ')', '') || 
case when is_nullable = 'YES' then ' NULL' else ' NOT NULL' end as column_expr
FROM information_schema.columns
WHERE table_schema || '.' || table_name = 'yourschema.yourtable'
ORDER BY ordinal_position
) column_list;