甚至根据@vkkeeper的响应进行了更多的修改。增加了从特定模式查询表的可能性。

CREATE OR REPLACE FUNCTION public.describe_table(p_schema_name character varying, p_table_name character varying)
  RETURNS SETOF text AS
$BODY$
DECLARE
    v_table_ddl   text;
    column_record record;
    table_rec record;
    constraint_rec record;
    firstrec boolean;
BEGIN
    FOR table_rec IN
        SELECT c.relname, c.oid FROM pg_catalog.pg_class c
            LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
                WHERE relkind = 'r'
                AND n.nspname = p_schema_name
                AND relname~ ('^('||p_table_name||')$')
          ORDER BY c.relname
    LOOP
        FOR column_record IN
            SELECT
                b.nspname as schema_name,
                b.relname as table_name,
                a.attname as column_name,
                pg_catalog.format_type(a.atttypid, a.atttypmod) as column_type,
                CASE WHEN
                    (SELECT substring(pg_catalog.pg_get_expr(d.adbin, d.adrelid) for 128)
                     FROM pg_catalog.pg_attrdef d
                     WHERE d.adrelid = a.attrelid AND d.adnum = a.attnum AND a.atthasdef) IS NOT NULL THEN
                    'DEFAULT '|| (SELECT substring(pg_catalog.pg_get_expr(d.adbin, d.adrelid) for 128)
                                  FROM pg_catalog.pg_attrdef d
                                  WHERE d.adrelid = a.attrelid AND d.adnum = a.attnum AND a.atthasdef)
                ELSE
                    ''
                END as column_default_value,
                CASE WHEN a.attnotnull = true THEN
                    'NOT NULL'
                ELSE
                    'NULL'
                END as column_not_null,
                a.attnum as attnum,
                e.max_attnum as max_attnum
            FROM
                pg_catalog.pg_attribute a
                INNER JOIN
                 (SELECT c.oid,
                    n.nspname,
                    c.relname
                  FROM pg_catalog.pg_class c
                       LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
                  WHERE c.oid = table_rec.oid
                  ORDER BY 2, 3) b
                ON a.attrelid = b.oid
                INNER JOIN
                 (SELECT
                      a.attrelid,
                      max(a.attnum) as max_attnum
                  FROM pg_catalog.pg_attribute a
                  WHERE a.attnum > 0
                    AND NOT a.attisdropped
                  GROUP BY a.attrelid) e
                ON a.attrelid=e.attrelid
            WHERE a.attnum > 0
              AND NOT a.attisdropped
            ORDER BY a.attnum
        LOOP
            IF column_record.attnum = 1 THEN
                v_table_ddl:='CREATE TABLE '||column_record.schema_name||'.'||column_record.table_name||' (';
            ELSE
                v_table_ddl:=v_table_ddl||',';
            END IF;

            IF column_record.attnum <= column_record.max_attnum THEN
                v_table_ddl:=v_table_ddl||chr(10)||
                         '    '||column_record.column_name||' '||column_record.column_type||' '||column_record.column_default_value||' '||column_record.column_not_null;
            END IF;
        END LOOP;

        firstrec := TRUE;
        FOR constraint_rec IN
            SELECT conname, pg_get_constraintdef(c.oid) as constrainddef
                FROM pg_constraint c
                    WHERE conrelid=(
                        SELECT attrelid FROM pg_attribute
                        WHERE attrelid = (
                            SELECT oid FROM pg_class WHERE relname = table_rec.relname
                                AND relnamespace = (SELECT ns.oid FROM pg_namespace ns WHERE ns.nspname = p_schema_name)
                        ) AND attname='tableoid'
                    )
        LOOP
            v_table_ddl:=v_table_ddl||','||chr(10);
            v_table_ddl:=v_table_ddl||'CONSTRAINT '||constraint_rec.conname;
            v_table_ddl:=v_table_ddl||chr(10)||'    '||constraint_rec.constrainddef;
            firstrec := FALSE;
        END LOOP;
        v_table_ddl:=v_table_ddl||');';
        RETURN NEXT v_table_ddl;
    END LOOP;
END;
$BODY$
  LANGUAGE plpgsql VOLATILE
  COST 100;

下面是对shekwi的查询稍加改进的版本。 它生成主键约束，并能够处理临时表:

with pkey as
(
    select cc.conrelid, format(E',
    constraint %I primary key(%s)', cc.conname,
        string_agg(a.attname, ', ' 
            order by array_position(cc.conkey, a.attnum))) pkey
    from pg_catalog.pg_constraint cc
        join pg_catalog.pg_class c on c.oid = cc.conrelid
        join pg_catalog.pg_attribute a on a.attrelid = cc.conrelid 
            and a.attnum = any(cc.conkey)
    where cc.contype = 'p'
    group by cc.conrelid, cc.conname
)
select format(E'create %stable %s%I\n(\n%s%s\n);\n',
    case c.relpersistence when 't' then 'temporary ' else '' end,
    case c.relpersistence when 't' then '' else n.nspname || '.' end,
    c.relname,
    string_agg(
        format(E'\t%I %s%s',
            a.attname,
            pg_catalog.format_type(a.atttypid, a.atttypmod),
            case when a.attnotnull then ' not null' else '' end
        ), E',\n'
        order by a.attnum
    ),
    (select pkey from pkey where pkey.conrelid = c.oid)) as sql
from pg_catalog.pg_class c
    join pg_catalog.pg_namespace n on n.oid = c.relnamespace
    join pg_catalog.pg_attribute a on a.attrelid = c.oid and a.attnum > 0
    join pg_catalog.pg_type t on a.atttypid = t.oid
where c.relname = :table_name
group by c.oid, c.relname, c.relpersistence, n.nspname;

使用table_name参数指定表的名称。

从linux命令行在postgresql中为一个表生成create table语句:

为演示创建一个表:

CREATE TABLE your_table(
    thekey   integer NOT NULL,  
    ticker   character varying(10) NOT NULL,
    date_val date,
    open_val numeric(10,4) NOT NULL
); 

Pg_dump手动，可以输出表创建PSQL语句:

pg_dump -U your_user your_database -t your_table --schema-only

打印:

-- pre-requisite database and table configuration omitted
CREATE TABLE your_table (
    thekey integer NOT NULL, 
    ticker character varying(10) NOT NULL, 
    date_val date,  
    open_val numeric(10,4) NOT NULL 
); 
-- post-requisite database and table configuration omitted
  

解释:

Pg_dump帮助我们获得关于数据库本身的信息。-U代表用户名。我的pgadmin用户没有设置密码，所以我不需要输入密码。-t选项表示指定一个表。——schema-only表示只打印关于表的数据，而不是表中的数据。

pg_dump是优秀的C代码，它试图很好地处理不断发展的sql标准，并处理在postgresql的查询语言和它在磁盘上的表示之间产生的成千上万个细节。如果你想卷自己的“psql磁盘创建语句”的安排，你是龙:https://doxygen.postgresql.org/pg__dump_8c_source.html

另一个绕过pg_dump的选项是在创建表时保存表创建SQL语句。把它放在安全的地方，需要的时候拿来。

或者使用SQL从postgresql中获取表名、列名和数据类型信息:

CREATE TABLE your_table(  thekey integer NOT NULL,
                          ticker character varying(10) NOT NULL,
                          date_val date,
                          open_val numeric(10,4) NOT NULL
); 

SELECT table_name, column_name, data_type 
FROM information_schema.columns 
WHERE table_name = 'your_table'; 

打印:

┌────────────┬─────────────┬───────────────────┐ 
│ table_name │ column_name │     data_type     │ 
├────────────┼─────────────┼───────────────────┤ 
│ your_table │ thekey      │ integer           │ 
│ your_table │ ticker      │ character varying │ 
│ your_table │ date_val    │ date              │ 
│ your_table │ open_val    │ numeric           │ 
└────────────┴─────────────┴───────────────────┘ 

如果你有PgAdmin4，那么打开它。转到您的数据库——>模式——>表——>右击要创建脚本的表名——> Scripts——> create script

pg_dump -t 'schema-name.table-name' --schema-only database-name

更多信息-在手册。

如果您不想创建函数，而只想让查询创建一个基本的表结构，这里有一个解决方案。

select 'CREATE TABLE ' || table_name ||'(' ||STRING_AGG (
    column_name || ' ' || data_type ,
        ','
       ORDER BY
        table_name,
        ordinal_position
    ) ||');'
    from 
information_schema.columns 
where table_schema = 'public'
group by 
table_name