还有另一个plpgsql -仅当max(att) >时重置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;
$$
;

另外注释行——execute format('alter sequence将给出列表，而不是实际重置值

我建议在postgres wiki上找到这个解决方案。它更新表的所有序列。

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):

保存到一个文件，输入'reset。sql' 运行该文件并以不包括通常头的方式保存其输出，然后运行该输出。例子:

例子:

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

原文(也修复了序列所有权)在这里

我找不到Rails的明确答案。

从rails控制台

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

例如将table_name替换为users。

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。

重置所有序列，除了每个表的主键是“id”外，对名称没有任何假设:

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%';

更新模式中用作ID的所有序列的方法:

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