摘要：
--INSTR函数 SELECT INSTR(' HELLO WORLD','H') FROM DUAL; --LTRIM RTRIM函数 SELECT LTRIM('*HELLO=','*') FROM DUAL; SELECT RTRIM('=HELLO=','=') FROM DUAL; SELECT RTRIM(LTRIM('*HELLO*','*'),'*') FROM DUAL; -... 阅读全文
摘要：
with temp as( select '湖北省' province,'武汉市' city,'第一' ranking from dual union all select '湖北省' province,'孝感市' city,'第二' ranking from dual union all select '湖北省' province,'宜昌市' city,'第三' ... 阅读全文