Log for YSITD
China hires over 100 TSMC engineers in push for chip leadership (Score: 100+ in 6 hours)
Link: https://readhacker.news/s/4tqup
Comments: https://readhacker.news/c/4tqup
Link: https://readhacker.news/s/4tqup
Comments: https://readhacker.news/c/4tqup
ＡＡ小編，你好
我叫做ＢＢ，是ＣＣ的ＤＤ，最近想要ＥＥ，目的是ＦＦ，主要用於ＧＧ，預期希望達成ＨＨ。
而我們這邊能夠提供ＩＩ，亦或者是ＬＬ方面的ＫＫ。
希望有機會可以得到ＡＡ的贊助、合作 m(_ _)m
我叫做ＢＢ，是ＣＣ的ＤＤ，最近想要ＥＥ，目的是ＦＦ，主要用於ＧＧ，預期希望達成ＨＨ。
而我們這邊能夠提供ＩＩ，亦或者是ＬＬ方面的ＫＫ。
希望有機會可以得到ＡＡ的贊助、合作 m(_ _)m
Any database God here? I wanna ask how should I design the MySQL database schemes?
Let say I got a table name called "car" which I used to store diff type of car like Tesla, Myvi, Proton
Now i need to store extra thing, like maybe Tesla got AI I'll need to store their AI attribute like AI version number; for Proton maybe he got aircorn, I need to store that aircorn production date; and Myvi got Aircorn, radio and GPS, and I need to store all their device attribute
Let say I got a table name called "car" which I used to store diff type of car like Tesla, Myvi, Proton
Now i need to store extra thing, like maybe Tesla got AI I'll need to store their AI attribute like AI version number; for Proton maybe he got aircorn, I need to store that aircorn production date; and Myvi got Aircorn, radio and GPS, and I need to store all their device attribute
还有一个问题是，我db有apple，pear，和banana 三个table，但是三个table都会foreign到一个class table（分等级）； 除了用polymorph还可以用什么
就是
Apple
1. YamiBrand, RM10, 1 (class id)
Pear
...
Banana
...
AppleFruitClass
1. Class A, 1
2. Class B, 1
3. Class C, 1
PearFruitClass
...
BananaFruitClass
...
Apple
1. YamiBrand, RM10, 1 (class id)
Pear
...
Banana
...
AppleFruitClass
1. Class A, 1
2. Class B, 1
3. Class C, 1
PearFruitClass
...
BananaFruitClass
...
你的例子有點不適合
Quality (*id, level, details)
Apple (*id, quality_id[fk=quality])
Banana (*id, quality_id[fk=quality])
Orange (*id, quality_id[fk=quality])
=>
Fruit (*id, type, quality)
Quality (*id, level, details)
Apple (*id, quality_id[fk=quality])
Banana (*id, quality_id[fk=quality])
Orange (*id, quality_id[fk=quality])
=>
Fruit (*id, type, quality)
你看人家pgsql: select * from fruits where data->'quality' = 'high'
還能自建Index expression
還能自建Index expression
看人家
CREATE INDEX article_hotness ON article (((LOG(GREATEST(vote_score, 0) + 1) * 287015) + (created_at / 1000)))
CREATE INDEX article_hotness ON article (((LOG(GREATEST(vote_score, 0) + 1) * 287015) + (created_at / 1000)))