哪个更好的大查询或多个小查询？

Question

哪个更好又有效？一个大的查询然后只是处理php中的获取查询或从php函数将只创建一个查询小数据的循环函数。请注意表格可以很大（数千个原始）。感谢。

评论表

list = [#items]
for item in list: #instead of a while loop
#do something 
    print item

预期输出为：

id | parent | msg
---+--------+---------      
1  |   0    | hello   
2  |   1    | hi      
3  |   2    | whats up       
4  |   3    | yow       
5  |   1    | hellow   
6  |   2    | nice       
7  |   0    | great   

Answer 1

  

根据经验，查询越少越好。

这是一个很好的问题，但已多次回答。

Is it better to return one big query or a few smaller ones?

Multiple small queries vs a single long query. Which one is more efficient?

One big query vs. many small ones?

Which one is faster single big query or few small queries?

What is faster, a big joined query with more PHP or multiple small selects with less PHP?

Should I use one big SQL Select statement or several small ones?

https://dba.stackexchange.com/questions/76973/what-is-faster-one-big-query-or-many-small-queries

https://dba.stackexchange.com/questions/35277/is-it-better-to-separate-a-big-query-into-multiple-smaller-queries