Tag:Average

  • DQL query statement

    Time:2021-1-19

    Sort query*Syntax: order by clause*Order by sort field 1, sort method 1, sort field 2, sort method 2 *Sort by: *ASC: ascending order, default. *Desc: descending order. *Note: *If there are multiple sorting conditions, the second condition will be judged only when the condition values of the current edge are the same. Aggregate function: a […]

  • Antutou released the Android mid end mobile phone performance list in May 2020, and MediaTek Tianji 1000L ranked first temporarily

    Time:2021-1-19

    Technical editor: Wang ZhizhiSegmentFault has he reported the official account number: SegmentFault Recently, antinu released the Android mid end mobile phone performance list in May 2020. According to the list, Lianfa Tianji 1000L has become the new generation of mid end performance king, surpassing Kirin, Xiaolong and exynos. Ranking first this month is oppo Reno […]

  • SQL sort

    Time:2020-11-26

    Sort 1, 2, 2, 2, 3, 4 with the following function: select row_ Number() over (order by field) from table name; 1、 row_number() Values: 1, 2, 2, 2, 3, 4 Sequence: 1, 2, 3, 4, 5, 6 2、rank() Values: 1, 2, 2, 2, 3, 4 Sequence: 1, 2, 2, 2, 5, 6 3、dense_rank() Values: 1, […]

  • [SQL interview question 2] MySQL and Oracle Database

    Time:2020-7-23

    1. If matched, update desc of dictb to corresponding field desc in dicta First create two tables: CREATE TABLE DictA(id1 number, desc1 varchar2(10)); CREATE TABLE DictB(id1 number, desc1 varchar2(10)); Insert into dicta values (1001, ‘fund’); Insert into dicta values (2001, ‘insurance’); Insert into dicta values (3001, ‘securities’); Insert into dicta values (3002, ‘trust’); Insert into […]

  • Is it feasible for RSI index to judge bitcoin price trend?

    Time:2020-6-3

    1. Principle of RSI index The relative strength index (RSI) was created by wells wider in June 1978. It is a kind of technical index to judge the internal strength of asset prices and predict the future direction of price changes by calculating the comparison of market buying and selling forces based on the changes […]

  • Oracle compute time format average

    Time:2019-11-3

    select to_char((to_date(‘2019-07-01’, ‘yyyy-mm-dd’) + numtodsinterval(avg(begin_time_second), ‘second’)),’hh24:mi:ss’) avg_begin_time,to_char((to_date(‘2019-07-01’, ‘yyyy-mm-dd’) + numtodsinterval(avg(end_time_second), ‘second’)),’hh24:mi:ss’) avg_end_time–2019-07-01 00:00:00 + numtodsinterval (average, ‘seconds’) is converted to date format and then to time character formatfrom (  select — convert working hours to seconds   to_char(a.actontime, ‘hh24’) * 3600 +   to_char(a.actontime, ‘mi’) * 60 +   to_char(a.actontime, ‘ss’) as begin_time_second,— convert off hours to seconds   to_char(a.actofftime, […]