作为一个非常困惑的新手,IF语句和、[]、( )、(( ))是怎么回事?if [ $jengnr -eq 1 ]; thenif [[ -f "$jdir$object.eng.dat" ]]; then#!/bin/bashif [ $1 -gt 100 ]echo Hey that\'s a large number.then
echo And is also an
所以我的查询应该是这样的select * from pushnotifications where ((from_user_id = $a或to_user_id = $a) and (from_user_id= $b或to_user_id = $b) or (to_user_id = $a and from_user_id = 0)) and id=$c