633

我遇到了我的主键序列与我的表行不同步的问题。

也就是说,当我插入一个新行时,我得到一个重复键错误,因为串行数据类型中隐含的序列返回一个已经存在的数字。

这似乎是由于导入/恢复没有正确维护顺序引起的。

4

32 回答 32

857
-- Login to psql and run the following

-- What is the result?
SELECT MAX(id) FROM your_table;

-- Then run...
-- This should be higher than the last result.
SELECT nextval('your_table_id_seq');

-- If it's not higher... run this set the sequence last to your highest id. 
-- (wise to run a quick pg_dump first...)

BEGIN;
-- protect against concurrent inserts while you update the counter
LOCK TABLE your_table IN EXCLUSIVE MODE;
-- Update the sequence
SELECT setval('your_table_id_seq', COALESCE((SELECT MAX(id)+1 FROM your_table), 1), false);
COMMIT;

来源 - Ruby 论坛

于 2008-10-28T18:14:13.750 回答
263

pg_get_serial_sequence可用于避免对序列名称的任何错误假设。这会一次性重置序列:

SELECT pg_catalog.setval(pg_get_serial_sequence('table_name', 'id'), (SELECT MAX(id) FROM table_name)+1);

或更简洁地说:

SELECT pg_catalog.setval(pg_get_serial_sequence('table_name', 'id'), MAX(id)) FROM table_name;

然而,这种形式不能正确处理空表,因为 max(id) 为空,你也不能设置 0,因为它超出了序列的范围。一种解决方法是使用ALTER SEQUENCE语法,即

ALTER SEQUENCE table_name_id_seq RESTART WITH 1;
ALTER SEQUENCE table_name_id_seq RESTART; -- 8.4 or higher

ALTER SEQUENCE用途有限,因为序列名称和重启值不能是表达式。

似乎最好的通用解决方案是setval使用 false 作为第三个参数调用,允许我们指定“下一个要使用的值”:

SELECT setval(pg_get_serial_sequence('t1', 'id'), coalesce(max(id),0) + 1, false) FROM t1;

这勾选了我所有的框:

  1. 避免对实际序列名称进行硬编码
  2. 正确处理空表
  3. 处理具有现有数据的表,并且不会在序列中留下漏洞

最后,请注意,pg_get_serial_sequence仅当序列由列拥有时才有效。如果递增列被定义为一种serial类型,则会出现这种情况,但是如果手动添加序列,则必须确保ALTER SEQUENCE .. OWNED BY也执行。

即,如果serialtype 用于创建表,这应该都可以工作:

CREATE TABLE t1 (
  id serial,
  name varchar(20)
);

SELECT pg_get_serial_sequence('t1', 'id'); -- returns 't1_id_seq'

-- reset the sequence, regardless whether table has rows or not:
SELECT setval(pg_get_serial_sequence('t1', 'id'), coalesce(max(id),0) + 1, false) FROM t1;

但是如果手动添加序列:

CREATE TABLE t2 (
  id integer NOT NULL,
  name varchar(20)
);

CREATE SEQUENCE t2_custom_id_seq
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;

ALTER TABLE t2 ALTER COLUMN id SET DEFAULT nextval('t2_custom_id_seq'::regclass);

ALTER SEQUENCE t2_custom_id_seq OWNED BY t2.id; -- required for pg_get_serial_sequence

SELECT pg_get_serial_sequence('t2', 'id'); -- returns 't2_custom_id_seq'

-- reset the sequence, regardless whether table has rows or not:
SELECT setval(pg_get_serial_sequence('t2', 'id'), coalesce(max(id),0) + 1, false) FROM t1;
于 2010-09-13T08:19:28.987 回答
160

最短最快的方法:

SELECT setval('tbl_tbl_id_seq', max(tbl_id)) FROM tbl;

tbl_id作为serialtable 的列tbl,从序列中提取tbl_tbl_id_seq(这是默认的自动名称)。

如果您不知道附加序列的名称(不必采用默认形式),请使用pg_get_serial_sequence()

SELECT setval(pg_get_serial_sequence('tbl', 'tbl_id'), max(tbl_id)) FROM tbl;

这里没有一个错误。手册:

双参数形式将序列的last_value字段设置为指定值并将其is_called字段设置为true,这意味着 下一个nextval将在返回值之前将序列推进。

大胆强调我的。

如果表可以为空并且在这种情况下实际上从 1 开始:

SELECT setval(pg_get_serial_sequence('tbl', 'tbl_id')
            , COALESCE(max(tbl_id) + 1, 1)
            , false)
FROM tbl;

我们不能只使用 2 参数形式并开始,0因为序列的下限默认为1(除非自定义)。

并发

为了防止并发序列活动或在上述查询中写入表,请将表锁定为模式SHARE。它可以防止并发事务写入更高的数字(或任何东西)。

还要考虑到客户端可能已经提前获取了序列号,而主表上没有任何锁,但是(可能在某些设置中发生),只增加序列的当前值,从不减少它。它可能看起来很偏执,但这与序列的性质和防御并发问题是一致的。

BEGIN;

LOCK TABLE tbl IN SHARE MODE;

SELECT setval('tbl_tbl_id_seq', max(tbl_id))
FROM   tbl
HAVING max(tbl_id) > (SELECT last_value FROM tbl_tbl_id_seq); -- prevent lower number

COMMIT;

SHARE模式足够强大。手册:

此模式保护表免受并发数据更改的影响。

它与ROW EXCLUSIVE模式冲突。

命令UPDATE,DELETEINSERT在目标表上获取此锁定模式

于 2014-04-30T14:07:28.977 回答
64

这将从公共重置所有序列,而不会对表或列名做出任何假设。在 8.4 版本上测试

CREATE OR REPLACE FUNCTION "reset_sequence" (tablename text, columnname text, sequence_name text) 
    RETURNS "pg_catalog"."void" AS 
    
    $body$  
      DECLARE 
      BEGIN 
    
      EXECUTE 'SELECT setval( ''' || sequence_name  || ''', ' || '(SELECT MAX(' || columnname || 
          ') FROM ' || tablename || ')' || '+1)';
    
      END;  
    
    $body$  LANGUAGE 'plpgsql';
    
    
SELECT table_name || '_' || column_name || '_seq', 
    reset_sequence(table_name, column_name, table_name || '_' || column_name || '_seq') 
FROM information_schema.columns where column_default like 'nextval%';
于 2010-11-04T21:03:13.957 回答
47

ALTER SEQUENCE sequence_name RESTART WITH (SELECT max(id) FROM table_name); 不工作。

复制自@tardate 答案:

SELECT setval(pg_get_serial_sequence('table_name', 'id'), MAX(id)) FROM table_name;
于 2008-12-10T08:29:11.830 回答
25

此命令仅用于更改 postgresql 中自动生成的键序列值

ALTER SEQUENCE "your_sequence_name" RESTART WITH 0;

代替零,您可以输入要重新启动序列的任何数字。

默认序列名称将"TableName_FieldName_seq". 例如,如果您的表名称是"MyTable"并且您的字段名称是"MyID",那么您的序列名称将是"MyTable_MyID_seq"

这是答案与@murugesanponappan 的答案相同,但他的解决方案中有语法错误。您不能(select max()...)alter命令中使用子查询。因此,要么您必须使用固定数值,要么您需要使用变量来代替子查询。

于 2014-09-01T10:29:48.710 回答
21

在下面的示例中,名是users架构名是public(默认架构),根据您的需要替换它。

1.检查最大id:

SELECT MAX(id) FROM public.users;

2. 检查下一个值:

SELECT nextval('public."users_id_seq"');

3. 如果next value低于max id,重置它:

SELECT setval('public."users_id_seq"',
  (SELECT MAX(id) FROM public.users)
);

笔记:

nextval()将在返回当前值之前增加序列,而currval()只返回当前值,如此所述。

于 2021-04-07T09:13:02.953 回答
20

重置所有序列,除了每个表的主键是“id”之外,没有关于名称的假设:

CREATE OR REPLACE FUNCTION "reset_sequence" (tablename text, columnname text)
RETURNS "pg_catalog"."void" AS
$body$
DECLARE
BEGIN
    EXECUTE 'SELECT setval( pg_get_serial_sequence(''' || tablename || ''', ''' || columnname || '''),
    (SELECT COALESCE(MAX(id)+1,1) FROM ' || tablename || '), false)';
END;
$body$  LANGUAGE 'plpgsql';

select table_name || '_' || column_name || '_seq', reset_sequence(table_name, column_name) from information_schema.columns where column_default like 'nextval%';
于 2013-01-31T19:00:43.067 回答
13

当序列名、列名、表名或模式名包含有趣的字符(如空格、标点符号等)时,这些函数充满了危险。我写了这个:

CREATE OR REPLACE FUNCTION sequence_max_value(oid) RETURNS bigint
VOLATILE STRICT LANGUAGE plpgsql AS  $$
DECLARE
 tabrelid oid;
 colname name;
 r record;
 newmax bigint;
BEGIN
 FOR tabrelid, colname IN SELECT attrelid, attname
               FROM pg_attribute
              WHERE (attrelid, attnum) IN (
                      SELECT adrelid::regclass,adnum
                        FROM pg_attrdef
                       WHERE oid IN (SELECT objid
                                       FROM pg_depend
                                      WHERE refobjid = $1
                                            AND classid = 'pg_attrdef'::regclass
                                    )
          ) LOOP
      FOR r IN EXECUTE 'SELECT max(' || quote_ident(colname) || ') FROM ' || tabrelid::regclass LOOP
          IF newmax IS NULL OR r.max > newmax THEN
              newmax := r.max;
          END IF;
      END LOOP;
  END LOOP;
  RETURN newmax;
END; $$ ;

您可以通过将 OID 传递给单个序列来调用它,它将返回具有默认序列的任何表使用的最大数字;或者您可以使用这样的查询运行它,以重置数据库中的所有序列:

 select relname, setval(oid, sequence_max_value(oid))
   from pg_class
  where relkind = 'S';

使用不同的 qual 您只能重置某个模式中的序列,依此类推。例如,如果您想调整“公共”模式中的序列:

select relname, setval(pg_class.oid, sequence_max_value(pg_class.oid))
  from pg_class, pg_namespace
 where pg_class.relnamespace = pg_namespace.oid and
       nspname = 'public' and
       relkind = 'S';

请注意,由于 setval() 的工作方式,您不需要将 1 添加到结果中。

作为结束语,我必须警告一些数据库似乎有默认链接到序列的方式,不让系统目录具有它们的完整信息。当您在 psql 的 \d 中看到这样的内容时,就会发生这种情况:

alvherre=# \d baz
                     Tabla «public.baz»
 Columna |  Tipo   |                 Modificadores                  
---------+---------+------------------------------------------------
 a       | integer | default nextval(('foo_a_seq'::text)::regclass)

请注意,除了 ::regclass 转换之外,该默认子句中的 nextval() 调用还有 ::text 转换。我认为这是由于数据库是从旧 PostgreSQL 版本进行 pg_dump 的。将会发生的是上面的函数 sequence_max_value() 将忽略这样的表。要解决此问题,您可以重新定义 DEFAULT 子句以直接引用序列而不进行强制转换:

alvherre=# alter table baz alter a set default nextval('foo_a_seq');
ALTER TABLE

然后 psql 正确显示:

alvherre=# \d baz
                     Tabla «public.baz»
 Columna |  Tipo   |             Modificadores              
---------+---------+----------------------------------------
 a       | integer | default nextval('foo_a_seq'::regclass)

一旦你解决了这个问题,这个函数就可以正确地用于这个表以及所有其他可能使用相同序列的表。

于 2011-05-09T22:20:43.500 回答
12

我建议在 postgres wiki 上找到这个解决方案。它会更新您的表格的所有序列。

SELECT 'SELECT SETVAL(' ||
       quote_literal(quote_ident(PGT.schemaname) || '.' || quote_ident(S.relname)) ||
       ', COALESCE(MAX(' ||quote_ident(C.attname)|| '), 1) ) FROM ' ||
       quote_ident(PGT.schemaname)|| '.'||quote_ident(T.relname)|| ';'
FROM pg_class AS S,
     pg_depend AS D,
     pg_class AS T,
     pg_attribute AS C,
     pg_tables AS PGT
WHERE S.relkind = 'S'
    AND S.oid = D.objid
    AND D.refobjid = T.oid
    AND D.refobjid = C.attrelid
    AND D.refobjsubid = C.attnum
    AND T.relname = PGT.tablename
ORDER BY S.relname;

如何使用(来自 postgres wiki):

  • 将此保存到文件中,例如“reset.sql”
  • 运行文件并以不包含通常标题的方式保存其输出,然后运行该输出。例子:

例子:

psql -Atq -f reset.sql -o temp
psql -f temp
rm temp

原始文章(也修复了序列所有权)在这里

于 2016-07-25T19:29:11.423 回答
10

另一个 plpgsql - 仅在以下情况下重置max(att) > then lastval

do --check seq not in sync
$$
declare
 _r record;
 _i bigint;
 _m bigint;
begin
  for _r in (
    SELECT relname,nspname,d.refobjid::regclass, a.attname, refobjid
    FROM   pg_depend    d
    JOIN   pg_attribute a ON a.attrelid = d.refobjid AND a.attnum = d.refobjsubid
    JOIN pg_class r on r.oid = objid
    JOIN pg_namespace n on n.oid = relnamespace
    WHERE  d.refobjsubid > 0 and  relkind = 'S'
   ) loop
    execute format('select last_value from %I.%I',_r.nspname,_r.relname) into _i;
    execute format('select max(%I) from %s',_r.attname,_r.refobjid) into _m;
    if coalesce(_m,0) > _i then
      raise info '%',concat('changed: ',_r.nspname,'.',_r.relname,' from:',_i,' to:',_m);
      execute format('alter sequence %I.%I restart with %s',_r.nspname,_r.relname,_m+1);
    end if;
  end loop;

end;
$$
;

还评论该行将--execute format('alter sequence给出列表,而不是实际重置值

于 2017-04-20T12:10:04.230 回答
9

从公共重置所有序列

CREATE OR REPLACE FUNCTION "reset_sequence" (tablename text) RETURNS "pg_catalog"."void" AS 
$body$  
  DECLARE 
  BEGIN 
  EXECUTE 'SELECT setval( ''' 
  || tablename  
  || '_id_seq'', ' 
  || '(SELECT id + 1 FROM "' 
  || tablename  
  || '" ORDER BY id DESC LIMIT 1), false)';  
  END;  
$body$  LANGUAGE 'plpgsql';

select sequence_name, reset_sequence(split_part(sequence_name, '_id_seq',1)) from information_schema.sequences
        where sequence_schema='public';
于 2010-09-24T11:40:30.393 回答
8

这个问题发生在我使用实体框架创建数据库然后用初始数据为数据库播种时,这使得序列不匹配。

我通过在为数据库播种后创建要运行的脚本来解决它:

DO
$do$
DECLARE tablename text;
BEGIN
    -- change the where statments to include or exclude whatever tables you need
    FOR tablename IN SELECT table_name FROM information_schema.tables WHERE table_schema='public' AND table_type='BASE TABLE' AND table_name != '__EFMigrationsHistory'
        LOOP
            EXECUTE format('SELECT setval(pg_get_serial_sequence(''"%s"'', ''Id''), (SELECT MAX("Id") + 1 from "%s"))', tablename, tablename);
    END LOOP;
END
$do$
于 2018-04-08T15:22:44.327 回答
7

这里有一些非常核心的答案,我假设在被问到这个问题的时候它曾经非常糟糕,因为这里的很多答案不适用于 9.3 版。自 8.0 版以来的文档为这个问题提供了答案:

SELECT setval('serial', max(id)) FROM distributors;

此外,如果您需要注意区分大小写的序列名称,您可以这样做:

SELECT setval('"Serial"', max(id)) FROM distributors;
于 2014-11-07T12:34:27.443 回答
6

我的版本使用第一个,带有一些错误检查......

BEGIN;
CREATE OR REPLACE FUNCTION reset_sequence(_table_schema text, _tablename text, _columnname text, _sequence_name text)
RETURNS pg_catalog.void AS
$BODY$
DECLARE
BEGIN
 PERFORM 1
 FROM information_schema.sequences
 WHERE
  sequence_schema = _table_schema AND
  sequence_name = _sequence_name;
 IF FOUND THEN
  EXECUTE 'SELECT setval( ''' || _table_schema || '.' || _sequence_name  || ''', ' || '(SELECT MAX(' || _columnname || ') FROM ' || _table_schema || '.' || _tablename || ')' || '+1)';
 ELSE
  RAISE WARNING 'SEQUENCE NOT UPDATED ON %.%', _tablename, _columnname;
 END IF;
END; 
$BODY$
 LANGUAGE 'plpgsql';

SELECT reset_sequence(table_schema, table_name, column_name, table_name || '_' || column_name || '_seq')
FROM information_schema.columns
WHERE column_default LIKE 'nextval%';

DROP FUNCTION reset_sequence(_table_schema text, _tablename text, _columnname text, _sequence_name text) ;
COMMIT;
于 2011-09-13T18:22:39.810 回答
5

把它们放在一起

CREATE OR REPLACE FUNCTION "reset_sequence" (tablename text) 
RETURNS "pg_catalog"."void" AS
$body$
DECLARE
BEGIN
  EXECUTE 'SELECT setval( pg_get_serial_sequence(''' || tablename || ''', ''id''),
  (SELECT COALESCE(MAX(id)+1,1) FROM ' || tablename || '), false)';
END;
$body$  LANGUAGE 'plpgsql';

将修复 'id'给定表的序列(例如,django 通常需要)。

于 2012-11-09T12:26:09.877 回答
5

重新检查公共模式函数中的所有序列

CREATE OR REPLACE FUNCTION public.recheck_sequence (
)
RETURNS void AS
$body$
DECLARE
  _table_name VARCHAR;
  _column_name VARCHAR;  
  _sequence_name VARCHAR;
BEGIN
  FOR _table_name IN SELECT tablename FROM pg_catalog.pg_tables WHERE schemaname = 'public' LOOP
    FOR _column_name IN SELECT column_name FROM information_schema.columns WHERE table_name = _table_name LOOP
        SELECT pg_get_serial_sequence(_table_name, _column_name) INTO _sequence_name;
        IF _sequence_name IS NOT NULL THEN 
            EXECUTE 'SELECT setval('''||_sequence_name||''', COALESCE((SELECT MAX('||quote_ident(_column_name)||')+1 FROM '||quote_ident(_table_name)||'), 1), FALSE);';
        END IF;
    END LOOP;   
  END LOOP;
END;
$body$
LANGUAGE 'plpgsql'
VOLATILE
CALLED ON NULL INPUT
SECURITY INVOKER
COST 100;
于 2015-06-02T10:15:43.347 回答
4

在我还没有尝试过代码之前:在下面我发布了适用于我的电脑 [Postgres 8.3] 的 Klaus 和 user457226 解决方案的 sql 代码版本,只对 Klaus 和我的版本进行了一些小的调整为user457226 之一。

克劳斯解决方案:

drop function IF EXISTS rebuilt_sequences() RESTRICT;
CREATE OR REPLACE FUNCTION  rebuilt_sequences() RETURNS integer as
$body$
  DECLARE sequencedefs RECORD; c integer ;
  BEGIN
    FOR sequencedefs IN Select
      constraint_column_usage.table_name as tablename,
      constraint_column_usage.table_name as tablename, 
      constraint_column_usage.column_name as columnname,
      replace(replace(columns.column_default,'''::regclass)',''),'nextval(''','') as sequencename
      from information_schema.constraint_column_usage, information_schema.columns
      where constraint_column_usage.table_schema ='public' AND 
      columns.table_schema = 'public' AND columns.table_name=constraint_column_usage.table_name
      AND constraint_column_usage.column_name = columns.column_name
      AND columns.column_default is not null
   LOOP    
      EXECUTE 'select max('||sequencedefs.columnname||') from ' || sequencedefs.tablename INTO c;
      IF c is null THEN c = 0; END IF;
      IF c is not null THEN c = c+ 1; END IF;
      EXECUTE 'alter sequence ' || sequencedefs.sequencename ||' restart  with ' || c;
   END LOOP;

   RETURN 1; END;
$body$ LANGUAGE plpgsql;

select rebuilt_sequences();

user457226 解决方案:

--drop function IF EXISTS reset_sequence (text,text) RESTRICT;
CREATE OR REPLACE FUNCTION "reset_sequence" (tablename text,columnname text) RETURNS bigint --"pg_catalog"."void"
AS
$body$
  DECLARE seqname character varying;
          c integer;
  BEGIN
    select tablename || '_' || columnname || '_seq' into seqname;
    EXECUTE 'SELECT max("' || columnname || '") FROM "' || tablename || '"' into c;
    if c is null then c = 0; end if;
    c = c+1; --because of substitution of setval with "alter sequence"
    --EXECUTE 'SELECT setval( "' || seqname || '", ' || cast(c as character varying) || ', false)'; DOES NOT WORK!!!
    EXECUTE 'alter sequence ' || seqname ||' restart with ' || cast(c as character varying);
    RETURN nextval(seqname)-1;
  END;
$body$ LANGUAGE 'plpgsql';

select sequence_name, PG_CLASS.relname, PG_ATTRIBUTE.attname,
       reset_sequence(PG_CLASS.relname,PG_ATTRIBUTE.attname)
from PG_CLASS
join PG_ATTRIBUTE on PG_ATTRIBUTE.attrelid = PG_CLASS.oid
join information_schema.sequences
     on information_schema.sequences.sequence_name = PG_CLASS.relname || '_' || PG_ATTRIBUTE.attname || '_seq'
where sequence_schema='public';
于 2011-03-09T21:50:40.803 回答
4

这个答案是 mauro 的副本。

drop function IF EXISTS rebuilt_sequences() RESTRICT;
CREATE OR REPLACE FUNCTION  rebuilt_sequences() RETURNS integer as
$body$
  DECLARE sequencedefs RECORD; c integer ;
  BEGIN
    FOR sequencedefs IN Select
      DISTINCT(constraint_column_usage.table_name) as tablename,
      constraint_column_usage.column_name as columnname,
      replace(replace(columns.column_default,'''::regclass)',''),'nextval(''','') as sequencename
      from information_schema.constraint_column_usage, information_schema.columns
      where constraint_column_usage.table_schema ='public' AND 
      columns.table_schema = 'public' AND columns.table_name=constraint_column_usage.table_name
      AND constraint_column_usage.column_name = columns.column_name
      AND columns.column_default is not null 
      ORDER BY sequencename
   LOOP    
      EXECUTE 'select max('||sequencedefs.columnname||') from ' || sequencedefs.tablename INTO c;
      IF c is null THEN c = 0; END IF;
      IF c is not null THEN c = c+ 1; END IF;
      EXECUTE 'alter sequence ' || sequencedefs.sequencename ||' minvalue '||c ||' start ' || c ||' restart  with ' || c;
   END LOOP;

   RETURN 1; END;
$body$ LANGUAGE plpgsql;

select rebuilt_sequences();
于 2016-06-16T19:05:14.787 回答
3

如果在加载自定义 SQL 数据以进行初始化时看到此错误,另一种避免这种情况的方法是:

而不是写:

INSERT INTO book (id, name, price) VALUES (1 , 'Alchemist' , 10),

id从初始数据中删除(主键)

INSERT INTO book (name, price) VALUES ('Alchemist' , 10),

这使 Postgres 序列保持同步!

于 2014-05-23T13:52:00.473 回答
3

要将所有序列重新启动为 1,请使用:

-- Create Function
CREATE OR REPLACE FUNCTION "sy_restart_seq_to_1" (
    relname TEXT
)
RETURNS "pg_catalog"."void" AS
$BODY$

DECLARE

BEGIN
    EXECUTE 'ALTER SEQUENCE '||relname||' RESTART WITH 1;';
END;
$BODY$

LANGUAGE 'plpgsql';

-- Use Function
SELECT 
    relname
    ,sy_restart_seq_to_1(relname)
FROM pg_class
WHERE relkind = 'S';
于 2016-09-01T14:53:11.997 回答
2

Klaus 的答案是最有用的,只是有点想念:你必须在 select 语句中添加 DISTINCT。

但是,如果您确定对于两个不同的表,没有表+列名可以等效,您也可以使用:

select sequence_name, --PG_CLASS.relname, PG_ATTRIBUTE.attname
       reset_sequence(split_part(sequence_name, '_id_seq',1))
from PG_CLASS
join PG_ATTRIBUTE on PG_ATTRIBUTE.attrelid = PG_CLASS.oid
join information_schema.sequences
     on information_schema.sequences.sequence_name = PG_CLASS.relname || '_' || PG_ATTRIBUTE.attname
where sequence_schema='public';

这是 user457226 解决方案的扩展,适用于某些感兴趣的列名不是“ID”的情况。

于 2011-03-09T21:05:52.010 回答
2

我花了一个小时试图让 djsnowsill 使用混合大小写表和列来处理数据库,然后由于 Manuel Darveau 的评论终于偶然发现了解决方案,但我想我可以让每个人都更清楚一点:

CREATE OR REPLACE FUNCTION "reset_sequence" (tablename text, columnname text)
RETURNS "pg_catalog"."void" AS
$body$
DECLARE
BEGIN
EXECUTE format('SELECT setval(pg_get_serial_sequence(''%1$I'', %2$L),
        (SELECT COALESCE(MAX(%2$I)+1,1) FROM %1$I), false)',tablename,columnname);
END;
$body$  LANGUAGE 'plpgsql';

SELECT format('%s_%s_seq',table_name,column_name), reset_sequence(table_name,column_name) 
FROM information_schema.columns WHERE column_default like 'nextval%';

这有以下好处:

  • 不假设 ID 列以特定方式拼写。
  • 不假设所有表都有一个序列。
  • 为混合大小写表/列名工作。
  • 使用格式更简洁。

解释一下,问题是pg_get_serial_sequence需要字符串来计算出你所指的内容,所以如果你这样做:

"TableName" --it thinks it's a table or column
'TableName' --it thinks it's a string, but makes it lower case
'"TableName"' --it works!

这是''%1$I''在格式字符串中使用实现''的,撇号1$表示第一个 arg,并I表示在引号中

于 2017-07-05T17:00:21.640 回答
2
select 'SELECT SETVAL(' || seq [ 1] || ', COALESCE(MAX('||column_name||')+1, 1) ) FROM '||table_name||';'
from (
       SELECT table_name, column_name, column_default, regexp_match(column_default, '''.*''') as seq
       from information_schema.columns
       where column_default ilike 'nextval%'
     ) as sequense_query
于 2019-03-10T16:53:07.717 回答
2

只需运行以下命令:

SELECT setval('my_table_seq', (SELECT max(id) FROM my_table));
于 2019-10-01T13:03:37.023 回答
1

尝试重新索引

更新:正如评论中所指出的,这是对原始问题的答复。

于 2008-10-28T18:10:55.397 回答
1

丑陋的黑客使用一些 shell 魔法来修复它,这不是一个很好的解决方案,但可能会激发其他有类似问题的人:)

pg_dump -s <DATABASE> | grep 'CREATE TABLE' | awk '{print "SELECT setval(#" $3 "_id_seq#, (SELECT MAX(id) FROM " $3 "));"}' | sed "s/#/'/g" | psql <DATABASE> -f -
于 2013-05-27T22:38:33.237 回答
1

一种更新架构中用作 ID 的所有序列的方法:

DO $$ DECLARE
  r RECORD;
BEGIN
FOR r IN (SELECT tablename, pg_get_serial_sequence(tablename, 'id') as sequencename
          FROM pg_catalog.pg_tables
          WHERE schemaname='YOUR_SCHEMA'
          AND tablename IN (SELECT table_name 
                            FROM information_schema.columns 
                            WHERE table_name=tablename and column_name='id')
          order by tablename)
LOOP
EXECUTE
        'SELECT setval(''' || r.sequencename || ''', COALESCE(MAX(id), 1), MAX(id) IS NOT null)
         FROM ' || r.tablename || ';';
END LOOP;
END $$;
于 2019-05-15T18:53:33.867 回答
1

所以我可以看出这个线程中没有足够的意见或重新发明的轮子,所以我决定增加一些趣味性。

下面是一个过程:

  • 专注于(仅影响)与表关联的序列
  • 适用于 SERIAL 和 GENERATED AS IDENTITY 列
  • 适用于 good_column_names 和 "BAD_column_123" 名称
  • 如果表为空,则自动分配相应序列的定义起始值
  • 允许仅影响特定序列(在 schema.table.column 表示法中)
  • 有预览模式
CREATE OR REPLACE PROCEDURE pg_reset_all_table_sequences(
    IN commit_mode BOOLEAN DEFAULT FALSE
,   IN mask_in TEXT DEFAULT NULL
) AS
$$
DECLARE
    sql_reset TEXT;
    each_sec RECORD;
    new_val TEXT;
BEGIN

sql_reset :=
$sql$
SELECT setval(pg_get_serial_sequence('%1$s.%2$s', '%3$s'), coalesce(max("%3$s"), %4$s), false) FROM %1$s.%2$s;
$sql$
;

FOR each_sec IN (

    SELECT
        quote_ident(table_schema) as table_schema
    ,   quote_ident(table_name) as table_name
    ,   column_name
    ,   coalesce(identity_start::INT, seqstart) as min_val
    FROM information_schema.columns
    JOIN pg_sequence ON seqrelid = pg_get_serial_sequence(quote_ident(table_schema)||'.'||quote_ident(table_name) , column_name)::regclass
    WHERE
        (is_identity::boolean OR column_default LIKE 'nextval%') -- catches both SERIAL and IDENTITY sequences

    -- mask on column address (schema.table.column) if supplied
    AND coalesce( table_schema||'.'||table_name||'.'||column_name = mask_in, TRUE )
)
LOOP

IF commit_mode THEN
    EXECUTE format(sql_reset, each_sec.table_schema, each_sec.table_name, each_sec.column_name, each_sec.min_val) INTO new_val;
    RAISE INFO 'Resetting sequence for: %.% (%) to %'
        ,   each_sec.table_schema
        ,   each_sec.table_name
        ,   each_sec.column_name
        ,   new_val
    ;
ELSE
    RAISE INFO 'Sequence found for resetting: %.% (%)'
        ,   each_sec.table_schema
        ,   each_sec.table_name
        ,   each_sec.column_name
    ;
END IF
;

END LOOP;

END
$$
LANGUAGE plpgsql
;

预览:

call pg_reset_all_table_sequences();

承诺:

call pg_reset_all_table_sequences(true);

仅指定您的目标表:

call pg_reset_all_table_sequences('schema.table.column');

于 2020-10-07T19:21:49.063 回答
0

这里有很多很好的答案。重新加载我的 Django 数据库后,我也有同样的需求。

但我需要:

  • 多合一功能
  • 一次可以修复一个或多个模式
  • 一次可以修复所有或只修复一张桌子
  • 还想要一个很好的方法来查看到底发生了什么变化,或者没有改变

这似乎与最初的要求非常相似。
感谢 Baldiry 和 Mauro 让我走上了正轨。

drop function IF EXISTS reset_sequences(text[], text) RESTRICT;
CREATE OR REPLACE FUNCTION reset_sequences(
    in_schema_name_list text[] = '{"django", "dbaas", "metrics", "monitor", "runner", "db_counts"}',
    in_table_name text = '%') RETURNS text[] as
$body$
  DECLARE changed_seqs text[];
  DECLARE sequence_defs RECORD; c integer ;
  BEGIN
    FOR sequence_defs IN
        select
          DISTINCT(ccu.table_name) as table_name,
          ccu.column_name as column_name,
          replace(replace(c.column_default,'''::regclass)',''),'nextval(''','') as sequence_name
          from information_schema.constraint_column_usage ccu,
               information_schema.columns c
          where ccu.table_schema = ANY(in_schema_name_list)
            and ccu.table_schema = c.table_schema
            AND c.table_name = ccu.table_name
            and c.table_name like in_table_name
            AND ccu.column_name = c.column_name
            AND c.column_default is not null
          ORDER BY sequence_name
   LOOP
      EXECUTE 'select max(' || sequence_defs.column_name || ') from ' || sequence_defs.table_name INTO c;
      IF c is null THEN c = 1; else c = c + 1; END IF;
      EXECUTE 'alter sequence ' || sequence_defs.sequence_name || ' restart  with ' || c;
      changed_seqs = array_append(changed_seqs, 'alter sequence ' || sequence_defs.sequence_name || ' restart with ' || c);
   END LOOP;
   changed_seqs = array_append(changed_seqs, 'Done');

   RETURN changed_seqs;
END
$body$ LANGUAGE plpgsql;

然后执行并查看更改运行:

select *
from unnest(reset_sequences('{"django", "dbaas", "metrics", "monitor", "runner", "db_counts"}'));

退货

activity_id_seq                          restart at 22
api_connection_info_id_seq               restart at 4
api_user_id_seq                          restart at 1
application_contact_id_seq               restart at 20
于 2020-05-16T03:31:35.247 回答
0

我找不到 Rails 的明确答案。

来自rails console

ActiveRecord::Base.connection.execute("SELECT setval(pg_get_serial_sequence('table_name', 'id'), MAX(id)) FROM table_name;")

替换table_nameusers例如。

于 2022-01-29T17:44:54.580 回答
-1

SELECT setval...使 JDBC 很糟糕,所以这是一种与 Java 兼容的方法:

-- work around JDBC 'A result was returned when none was expected.'
-- fix broken nextval due to poorly written 20140320100000_CreateAdminUserRoleTables.sql
DO 'BEGIN PERFORM setval(pg_get_serial_sequence(''admin_user_role_groups'', ''id''), 1 + COALESCE(MAX(id), 0), FALSE) FROM admin_user_role_groups; END;';
于 2015-05-21T17:01:06.987 回答