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Get Root Directory Path of a PHP project
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this is just awesome, I tried $_SERVER['DOCUMENT_ROOT'], dirname(), $_SERVER['SCRIPT_NAME'] etc. but this worked excellently!
– webblover
Nov 26 '14 at 16:40
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MySQL CONCAT returns NULL if any field contain NULL
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mysql has IFNULL(arg, default) instead COALESCE with the same syntax
– Vasilii Suricov
Feb 19 '19 at 17:58
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SQLAlchemy IN clause
...is using raw SQL mode with SQLAlchemy, I use SQLAlchemy 0.9.8, python 2.7, MySQL 5.X, and MySQL-Python as connector, in this case, a tuple is needed. My code listed below:
id_list = [1, 2, 3, 4, 5] # in most case we have an integer list or set
s = text('SELECT id, content FROM myTable WHERE id IN :...
SQL - using alias in Group By
...OUP BY is executed before the SELECT clause.
There are exceptions though: MySQL and Postgres seem to have additional smartness that allows it.
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How do you run your own code alongside Tkinter's event loop?
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Use the after method on the Tk object:
from tkinter import *
root = Tk()
def task():
print("hello")
root.after(2000, task) # reschedule event in 2 seconds
root.after(2000, task)
root.mainloop()
Here's the declaration and documentation for the after method:
def after(self,...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
如何选择机器学习算法Choosing-a-Machine-Learning-Classifier机器学习 算法如何针对某个分类问题决定使用何种机器学习算法? 当然,如果你真心在乎准确率,最好的途径就是测试一大堆各式各样的算法(同时确保在每个算法上也测试...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
如何选择机器学习算法Choosing-a-Machine-Learning-Classifier机器学习 算法如何针对某个分类问题决定使用何种机器学习算法? 当然,如果你真心在乎准确率,最好的途径就是测试一大堆各式各样的算法(同时确保在每个算法上也测试...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
如何选择机器学习算法Choosing-a-Machine-Learning-Classifier机器学习 算法如何针对某个分类问题决定使用何种机器学习算法? 当然,如果你真心在乎准确率,最好的途径就是测试一大堆各式各样的算法(同时确保在每个算法上也测试...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
如何选择机器学习算法Choosing-a-Machine-Learning-Classifier机器学习 算法如何针对某个分类问题决定使用何种机器学习算法? 当然,如果你真心在乎准确率,最好的途径就是测试一大堆各式各样的算法(同时确保在每个算法上也测试...
如何选择机器学习算法 - 大数据 & AI - 清泛网 - 专注IT技能提升
如何选择机器学习算法Choosing-a-Machine-Learning-Classifier机器学习 算法如何针对某个分类问题决定使用何种机器学习算法? 当然,如果你真心在乎准确率,最好的途径就是测试一大堆各式各样的算法(同时确保在每个算法上也测试...