列出所有列在Postgres db8.1SQL

Question

我是转换一个数据库从postgres to mysql.

因为我找不到一个工具，不会欺骗自己，我会把所有postgres序，以自动增量ids in mysql与自动增量值。

所以，我怎么可以列出所有的序列中的一个 Postgres DB(8.1 版本)有关的信息表在其它的使用，未来价值等SQL query?

要知道，我不能使用 information_schema.sequences 看在8.4释放。

Answer 1

下面的查询给出了所有序列的名称。

SELECT c.relname FROM pg_class c WHERE c.relkind = 'S';

典型地，序列被命名为${table}_id_seq。简单的regex模式匹配会给你的表名。

要得到的序列的最后一个值使用以下查询：

SELECT last_value FROM test_id_seq;

Answer 2

请注意，从8.4的PostgreSQL开始就可以得到所有关于通过在数据库中使用的序列信息：

SELECT * FROM information_schema.sequences;

---

由于我使用的是更高版本的PostgreSQL（9.1），并寻找相同的答案高低，我说这个答案留给后人的缘故，并为未来的搜索。

Answer 3

执行命令psql -E，然后\ds

Answer 4

疼痛的一点点后，我得到它。

实现这一目标的最佳方式是列出所有表

select * from pg_tables where schemaname = '<schema_name>'

和然后，对于每一个表中，列出的所有列与属性

select * from information_schema.columns where table_name = '<table_name>'

然后，对于每一列，测试它是否有一个序列

select pg_get_serial_sequence('<table_name>', '<column_name>')

和然后，获得关于该序列的信息

select * from <sequence_name>

Answer 5

自动生成的序列（例如用于SERIAL列创建）和父表之间的关系是由序列所有者属性建模。

可以使用所拥有的 ALTER SEQUENCE修改此关系条命令

e.g。      ALTER SEQUENCE foo_id通过foo_schema.foo_table国有

将其设置为被链接到表格foo_table

或      ALTER SEQUENCE foo_id通过NONE国有

打破序列和任何表之间的连接

关于该关系的信息被存储在 pg_depend目录表。

的接合关系是pg_depend.objid之间的链路 - > WHERE pg_class.oid = relkind 'S' - 其中序列链接到加入记录，然后pg_depend.refobjid - > WHERE pg_class.oid = relkind 'R'，一个把该连接记录所属关系（表）

这个查询返回所有的序列 - >在数据库表中的依赖关系。 where子句它过滤为仅包括自动生成的关系，这会限制由SERIAL类型列创建仅显示序列。

WITH fq_objects AS (SELECT c.oid,n.nspname || '.' ||c.relname AS fqname , 
                           c.relkind, c.relname AS relation 
                    FROM pg_class c JOIN pg_namespace n ON n.oid = c.relnamespace ),

     sequences AS (SELECT oid,fqname FROM fq_objects WHERE relkind = 'S'),  
     tables    AS (SELECT oid, fqname FROM fq_objects WHERE relkind = 'r' )  
SELECT
       s.fqname AS sequence, 
       '->' as depends, 
       t.fqname AS table 
FROM 
     pg_depend d JOIN sequences s ON s.oid = d.objid  
                 JOIN tables t ON t.oid = d.refobjid  
WHERE 
     d.deptype = 'a' ;

Answer 6

序列信息：最大值

SELECT * FROM information_schema.sequences;

序列信息：最后一个值

SELECT * FROM <sequence_name>

Answer 7

我知道这个职位是很老，但我发现 CMS 解决方案是非常有用的，因为我一直在寻找一个自动化的方式来序列链接到表和列，并希望分享。使用 pg_depend 目录表中是关键。我扩大了什么做的目的是：

WITH fq_objects AS (SELECT c.oid,n.nspname || '.' ||c.relname AS fqname ,
                           c.relkind, c.relname AS relation
                    FROM pg_class c JOIN pg_namespace n ON n.oid = c.relnamespace ),

     sequences AS (SELECT oid,fqname FROM fq_objects WHERE relkind = 'S'),
     tables    AS (SELECT oid, fqname FROM fq_objects WHERE relkind = 'r' )
SELECT
       s.fqname AS sequence,
       '->' as depends,
       t.fqname AS table,
       a.attname AS column
FROM
     pg_depend d JOIN sequences s ON s.oid = d.objid
                 JOIN tables t ON t.oid = d.refobjid
                 JOIN pg_attribute a ON a.attrelid = d.refobjid and a.attnum = d.refobjsubid
WHERE
     d.deptype = 'a' ;

此版本增加列返回字段的列表。与这两个表名在手，列名，将呼叫 pg_set_serial_sequence 可以很容易地保证数据库中的所有序列的设置是否正确。例如：

CREATE OR REPLACE FUNCTION public.reset_sequence(tablename text, columnname text)
 RETURNS void
 LANGUAGE plpgsql
AS $function$
DECLARE
    _sql VARCHAR := '';
BEGIN
    _sql := $$SELECT setval( pg_get_serial_sequence('$$ || tablename || $$', '$$ || columnname || $$'), (SELECT COALESCE(MAX($$ || columnname || $$),1) FROM $$ || tablename || $$), true)$$;
    EXECUTE _sql;
END;
$function$;

希望这可以帮助别人与复位序列！

Answer 8

部分进行测试，但看起来基本完成。

select *
  from (select n.nspname,c.relname,
               (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) as def
          from pg_class c, pg_attribute a, pg_namespace n
         where c.relkind='r'
           and c.oid=a.attrelid
           and n.oid=c.relnamespace
           and a.atthasdef
           and a.atttypid=20) x
 where x.def ~ '^nextval'
 order by nspname,relname;

信贷，信贷是由于......它的部分逆转从SQL工程从\ d登录一个已知的表有一个序列。我敢肯定，这可能是更清洁过，但是，嘿，性能是不是一个问题。

Answer 9

一劈的种类，但尝试：

  

选择 '选择 ''' || relname || “”“如序列，从LAST_VALUE” || relname || “联盟”   从pg_catalog.pg_classÇ   WHERE c.relkind IN（ 'S'， ''）;

删除最后UNION并执行结果

Answer 10

先前答案的改进：

select string_agg('select sequence_name, last_value from ' || relname, chr(13) || 'union' || chr(13) order by relname) 
from pg_class where relkind ='S'

Answer 11

本声明列出了表和列与每一个顺序：

代码:

    SELECT t.relname as related_table, 
           a.attname as related_column,
           s.relname as sequence_name
    FROM pg_class s 
      JOIN pg_depend d ON d.objid = s.oid 
      JOIN pg_class t ON d.objid = s.oid AND d.refobjid = t.oid 
      JOIN pg_attribute a ON (d.refobjid, d.refobjsubid) = (a.attrelid, a.attnum)
      JOIN pg_namespace n ON n.oid = s.relnamespace 
    WHERE s.relkind     = 'S' 

  AND n.nspname     = 'public'

更多的在这里看到的 链接的答案

Answer 12

经由DEFAULT子句的解析每个表的每列中获取序列。此方法提供的即将哪一列序列被连接信息，并且不使用依赖性其可以不存在一些序列。即使pg_get_serial_sequence(sch.nspname||'.'||tbl.relname, col.attname)功能发现的不是所有的我的序列！

解决方案：

SELECT
    seq_sch.nspname  AS sequence_schema
  , seq.relname      AS sequence_name
  , seq_use."schema" AS used_in_schema
  , seq_use."table"  AS used_in_table
  , seq_use."column" AS used_in_column
FROM pg_class seq
  INNER JOIN pg_namespace seq_sch ON seq_sch.oid = seq.relnamespace
  LEFT JOIN (
              SELECT
                  sch.nspname AS "schema"
                , tbl.relname AS "table"
                , col.attname AS "column"
                , regexp_split_to_array(
                      TRIM(LEADING 'nextval(''' FROM
                           TRIM(TRAILING '''::regclass)' FROM
                                pg_get_expr(def.adbin, tbl.oid, TRUE)
                           )
                      )
                      , '\.'
                  )           AS column_sequence
              FROM pg_class tbl --the table
                INNER JOIN pg_namespace sch ON sch.oid = tbl.relnamespace
                --schema
                INNER JOIN pg_attribute col ON col.attrelid = tbl.oid
                --columns
                INNER JOIN pg_attrdef def ON (def.adrelid = tbl.oid AND def.adnum = col.attnum) --default values for columns
              WHERE tbl.relkind = 'r' --regular relations (tables) only
                    AND col.attnum > 0 --regular columns only
                    AND def.adsrc LIKE 'nextval(%)' --sequences only
            ) seq_use ON (seq_use.column_sequence [1] = seq_sch.nspname AND seq_use.column_sequence [2] = seq.relname)
WHERE seq.relkind = 'S' --sequences only
ORDER BY sequence_schema, sequence_name;

请注意1个序列可以在多个表中被使用，所以它可以在这里多行中列出。

Answer 13

感谢您的帮助。

下面是PL / pgSQL函数哪个更新数据库的每个序列。

---------------------------------------------------------------------------------------------------------
--- Nom : reset_sequence
--- Description : Générique - met à jour les séquences au max de l'identifiant
---------------------------------------------------------------------------------------------------------

CREATE OR REPLACE FUNCTION reset_sequence() RETURNS void AS 
$BODY$
DECLARE _sql VARCHAR := '';
DECLARE result threecol%rowtype; 
BEGIN
FOR result IN 
WITH fq_objects AS (SELECT c.oid,n.nspname || '.' ||c.relname AS fqname ,c.relkind, c.relname AS relation FROM pg_class c JOIN pg_namespace n ON n.oid = c.relnamespace ),
    sequences AS (SELECT oid,fqname FROM fq_objects WHERE relkind = 'S'),
    tables    AS (SELECT oid, fqname FROM fq_objects WHERE relkind = 'r' )
SELECT
       s.fqname AS sequence,
       t.fqname AS table,
       a.attname AS column
FROM
     pg_depend d JOIN sequences s ON s.oid = d.objid
                 JOIN tables t ON t.oid = d.refobjid
                 JOIN pg_attribute a ON a.attrelid = d.refobjid and a.attnum = d.refobjsubid
WHERE
     d.deptype = 'a' 
LOOP
     EXECUTE 'SELECT setval('''||result.col1||''', COALESCE((SELECT MAX('||result.col3||')+1 FROM '||result.col2||'), 1), false);';
END LOOP;
END;$BODY$ LANGUAGE plpgsql;

SELECT * FROM reset_sequence();

Answer 14

下面是另一个其具有序列名称旁边的模式名称

select nspname,relname from pg_class c join pg_namespace n on c.relnamespace=n.oid where relkind = 'S' order by nspname

Answer 15

此功能显示每个序列的LAST_VALUE。

它输出一个2列的表，该序列名称说再加上它的最后生成的值。

drop function if exists public.show_sequence_stats();
CREATE OR REPLACE FUNCTION public.show_sequence_stats()
    RETURNS TABLE(tablename text, last_value bigint) 
    LANGUAGE 'plpgsql'
    COST 100
    VOLATILE 
    ROWS 1000
AS $BODY$
declare r refcursor; rec record; dynamic_query varchar;
        BEGIN
            dynamic_query='select tablename,last_value from (';
            open r for execute 'select nspname,relname from pg_class c join pg_namespace n on c.relnamespace=n.oid where relkind = ''S'' order by nspname'; 
            fetch next from r into rec;
            while found 
            loop
                dynamic_query=dynamic_query || 'select '''|| rec.nspname || '.' || rec.relname ||''' "tablename",last_value from ' || rec.nspname || '.' || rec.relname || ' union all ';
                fetch next from r into rec; 
            end loop;
            close r; 
            dynamic_query=rtrim(dynamic_query,'union all') || ') x order by last_value desc;';
            return query execute dynamic_query;
        END;
$BODY$;

select * from show_sequence_stats();

Answer 16

假设在此篇 https://stackoverflow.com/a/46721603/653539 时，序列声明一起exec()功能与他们的最后值可使用单个查询中获取：

select s.sequence_schema, s.sequence_name,
  (select * from exec('select last_value from ' || s.sequence_schema || '.' || s.sequence_name) as e(lv bigint)) last_value
from information_schema.sequences s