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What is cardinality in MySQL?
What is cardinality in MySQL? Please explain in simple, non-technical language.
8 Answers
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What's the difference between using INDEX vs KEY in MySQL?
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When looking at table info in the latest version of SQLYog it shows KEY keyname (column_name) when I created the table with INDEX keyname (column_name). The fact that it is a synonym explains it perfectly.
– crmpicco
Apr 2 '14 at 10:10
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为什么我们程序员写不出好代码？ - 杂谈 - 清泛网 - 专注C/C++及内核技术
...网络游戏中的玩家，他们将更加关心自己的排名，而不是如何让代码更好。
开发者的重点变成了统计代码所编写的行数、解决bug或把所统计的提交的仓库里。如果代码行数都计算在内的话，原本一个问题只需10行代码即可解决...
Database, Table and Column Naming Conventions? [closed]
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I recommend checking out Microsoft's SQL Server sample databases:
https://github.com/Microsoft/sql-server-samples/releases/tag/adventureworks
The AdventureWorks sample uses a very clear and consistent naming convention that uses schema names for the organizatio...
Checking if a field contains a string
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https://docs.mongodb.com/manual/reference/sql-comparison/
http://php.net/manual/en/mongo.sqltomongo.php
MySQL
SELECT * FROM users WHERE username LIKE "%Son%"
MongoDB
db.users.find({username:/Son/})
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LINQ - Left Join, Group By, and Count
Let's say I have this SQL:
5 Answers
5
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Simple calculations for working with lat/lon and km distance?
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Why not use properly formulated geospatial queries???
Here is the SQL server reference page on the STContains geospatial function:
https://docs.microsoft.com/en-us/sql/t-sql/spatial-geography/stcontains-geography-data-type?view=sql-server-ver15
or if you do not waant to use box and radian...
Entity Framework .Remove() vs. .DeleteObject()
...tate is Deleted after that.) If you call SaveChanges afterwards EF sends a SQL DELETE statement to the database. If no referential constraints in the database are violated the entity will be deleted, otherwise an exception is thrown.
EntityCollection.Remove(childEntity) marks the relationship betwee...
MySQL Error 1153 - Got a packet bigger than 'max_allowed_packet' bytes
I'm importing a MySQL dump and getting the following error.
14 Answers
14
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How to convert an entire MySQL database characterset and collation to UTF-8?
How can I convert entire MySQL database character-set to UTF-8 and collation to UTF-8?
19 Answers
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