mysql根据查询结果批量更新多条数据(插入或更新)html
1.1 前言mysql
mysql根据查询结果执行批量更新或插入时常常会遇到1093的错误问题。基本上批量插入或新增都会涉及到子查询,mysql是建议不要对须要操做的表放入子查询条件中的,所以咱们尽可能避免子查询中涉及到须要操做的表,若是没法避免,则能够考虑用链接查询的方式进行。sql
ERROR 1093 (HY000): You can't specify target table 'dir' for update in FROM clausepost
1.2 根据查询结果批量更新spa
- 批量更新另外一张表的查询结果:
updatecode
file_directory_info dir
left joinhtmfile_directory_temp dirTemp
onblogdirTemp.pk_id > 1000ci
andget
dirTemp.dir_category = dir.dir_category
set
dir.parent_id = dirTemp.pk_id,
dir.dir_level = 2,
dir.dir_seq = concat('.',dirTemp.pk_id, dir.dir_seq)
where dir.dir_level is null;
1.3 根据查询结果批量新增
- 直接新增另外一张表的查询结果:
insert into file_directory_info (pk_id, dir_category, dir_seq, dir_name, parent_id) select (dictid + 1000) as pk_id, dictid as dir_category, concat('.',(dictid + 1000),'.') as dir_seq, dictname as dir_name, 0 as parent_id from dict_entry dict where dict.dictTypeid = 'HTCM_FILE_CLASSIFICTION' ;