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Convert from MySQL datetime to another format with PHP
I have a datetime column in MySQL.
18 Answers
18
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MySQL: Large VARCHAR vs. TEXT?
I've got a messages table in MySQL which records messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserte...
MySQL select one column DISTINCT, with corresponding other columns
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@Full Decent you can't, according to MySQL documentation: "The server is free to choose any value from each group, so unless they are the same, the values chosen are indeterminate.". In practice I've successfully used this kind of queries with ORDER BY clause, ...
os.walk without digging into directories below
... os.path.isdir(some_dir)
num_sep = some_dir.count(os.path.sep)
for root, dirs, files in os.walk(some_dir):
yield root, dirs, files
num_sep_this = root.count(os.path.sep)
if num_sep + level <= num_sep_this:
del dirs[:]
It works just like os.walk, but y...
select * vs select column
...the top of my head is when you want only the value of an indexed column in MySQL (for example, just to check for row existence), and you're using MyISAM storage engine, it'll grab the data from the MYI file, which could be in memory, and not even go to disk!
– Mike Sherov
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MySQL Conditional Insert
...his, dual is a table with one row only (found originally in Oracle, now in mysql too). The logic is that the SELECT statement generates a single row of data with the required values, but only when the values are not already found.
Alternatively, look at the MERGE statement.
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Deep Learning（深度学习）学习笔记整理系列之（二） - 大数据 & AI - 清泛...
...，不妨把这个碎片标记为 T。
他们提出的问题是，如何从这400个碎片中，选取一组碎片，S[k], 通过叠加的办法，合成出一个新的碎片，而这个新的碎片，应当与随机选择的目标碎片 T，尽可能相似，同时，S[k] 的数量尽可...
MySQL and GROUP_CONCAT() maximum length
I'm using GROUP_CONCAT() in a MySQL query to convert multiple rows into a single string.
However, the maximum length of the result of this function is 1024 characters.
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App Inventor 2 中文网原创内容 · App Inventor 2 中文网
...科普】App Inventor 2 添加超过10个屏幕会怎样？
【算法】如何计算1加到100的总和？（经典循环的写法）
【算法】App Inventor 2 算法之二分算法（Binary Search）实现，快速查找定位
组件用法
【微数据库】每次打开app时保持上一...
Does MySQL index foreign key columns automatically?
Does MySQL index foreign key columns automatically?
9 Answers
9
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