我遇到了一个问题,我的主键序列与我的表行不同步。

也就是说,当我插入一个新行时,我得到一个重复的键错误,因为在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/恢复没有正确地维护序列造成的。


当前回答

ALTER SEQUENCE sequence_name RESTART WITH (SELECT max(id) FROM table_name); 是行不通的。

复制自@tardate答案:

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

其他回答

试着重建索引。

更新:正如评论中指出的,这是对最初问题的回答。

这个答案是从毛罗那里抄来的。

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();
-- 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

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;

ALTER SEQUENCE sequence_name RESTART WITH (SELECT max(id) FROM table_name); 是行不通的。

复制自@tardate答案:

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