我正在尝试在数据库中合并3个表,因此在新表中,我将具有eventID,eventTitle,catDesc,containerName,evStartDate,evEndDate,evPrice字段。但是,当我尝试在阅读页面上实时查看它们时,总是会出现重复记录。我不太擅长MySQL,所以如果有人可以帮助我,我将不胜感激
NE_events
eventID eventTitle eventDesc evStartDate evEndDate evPrice
--------- ---------- ---------- --------- ------- -----------
1 Sherlock ... 04-07-20 05-07-20 £30.56
2 Live Rugby ... 07-05-20 09-05-20 £8.56
3 2020 tour .... 11-11-20 15-12-20 £20.57
NE_category
catID catDesc
------ -------
c1 family
c2 action
c3 comedy
NE_venue
venueID venueName location
------- --------- ---------
v1 Playhouse Manchester
v2 Royal Arena London
v3 RDS stadium Dublin
Syntax
-----
SELECT eventID, eventTitle, catDesc, venueName, evStartDate, evEndDate, evPrice FROM NE_events, NE_category, NE_venue ORDER BY eventTitle
恐怕这没有任何意义。您的记录之间没有外键关系。您如何判断一个表的哪个记录应该与其他两个表的记录匹配?关于外键,这确实很简单:https://www.w3schools.com/sql/sql_foreignkey.asp