生成创建特定表背后的SQL (DDL)。 我们可以简单地使用这个SQL查询-

SHOW TABLE your_schema_name.your_table_name

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

更多信息-在手册。

pg_dump -h XXXXXXXXXXX.us-west-1.rds.amazonaws.com -U anyuser -t tablename -s

如果您想一次对多个表执行此操作，则需要多次使用-t开关(我花了一些时间才弄清楚为什么逗号分隔的列表不起作用)。此外，将结果发送到外文件或管道到另一台机器上的postgres服务器也很有用

pg_dump -t table1 -t table2 database_name --schema-only > dump.sql

pg_dump -t table1 -t table2 database_name --schema-only | psql -h server_name database_name

下面是一条语句，它将为指定模式(包括约束)中的单个表生成DDL。

SELECT 'CREATE TABLE ' || pn.nspname || '.' || pc.relname || E'(\n' ||
   string_agg(pa.attname || ' ' || pg_catalog.format_type(pa.atttypid, pa.atttypmod) || coalesce(' DEFAULT ' || (
                                                                                                               SELECT pg_catalog.pg_get_expr(d.adbin, d.adrelid)
                                                                                                               FROM pg_catalog.pg_attrdef d
                                                                                                               WHERE d.adrelid = pa.attrelid
                                                                                                                 AND d.adnum = pa.attnum
                                                                                                                 AND pa.atthasdef
                                                                                                               ),
                                                                                                 '') || ' ' ||
              CASE pa.attnotnull
                  WHEN TRUE THEN 'NOT NULL'
                  ELSE 'NULL'
              END, E',\n') ||
   coalesce((SELECT E',\n' || string_agg('CONSTRAINT ' || pc1.conname || ' ' || pg_get_constraintdef(pc1.oid), E',\n' ORDER BY pc1.conindid)
            FROM pg_constraint pc1
            WHERE pc1.conrelid = pa.attrelid), '') ||
   E');'
FROM pg_catalog.pg_attribute pa
JOIN pg_catalog.pg_class pc
    ON pc.oid = pa.attrelid
    AND pc.relname = 'table_name'
JOIN pg_catalog.pg_namespace pn
    ON pn.oid = pc.relnamespace
    AND pn.nspname = 'schema_name'
WHERE pa.attnum > 0
    AND NOT pa.attisdropped
GROUP BY pn.nspname, pc.relname, pa.attrelid;

(注意-此解决方案不适用于PostgreSQL v12+)

我的解决方案是使用psql和-E选项登录postgres db，如下所示:

psql -E -U username -d database   

在psql中，运行以下命令查看postgres用来生成的sql 描述表语句:

-- List all tables in the schema (my example schema name is public)
\dt public.*
-- Choose a table name from above
-- For create table of one public.tablename
\d+ public.tablename  

基于运行这些描述命令后返回的sql，我能够把它们放在一起 下面是PLPGSQL函数:

CREATE OR REPLACE FUNCTION generate_create_table_statement(p_table_name varchar)
  RETURNS text AS
$BODY$
DECLARE
    v_table_ddl   text;
    column_record record;
BEGIN
    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.relname ~ ('^('||p_table_name||')$')
                AND pg_catalog.pg_table_is_visible(c.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;

    v_table_ddl:=v_table_ddl||');';
    RETURN v_table_ddl;
END;
$BODY$
  LANGUAGE 'plpgsql' COST 100.0 SECURITY INVOKER;

下面是函数用法:

SELECT generate_create_table_statement('tablename');

下面是drop语句，如果你不想让这个函数永久保存:

DROP FUNCTION generate_create_table_statement(p_table_name varchar);