Oracle Date Functions The Complete Guide
转载:Oracle Date Functions: The Complete Guide - Database Star
There are many different date and time functions in Oracle, and they behave differently than other databases. Learn what they are and see some useful queries in this article.
Oracle date functions are any functions that work with date...
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PL/SQL Record types, Bulk Collect, and Collections.
转载:PL/SQL Tutorial: Chapter 6 - Database Star
In this chapter, we’ll learn about:
Using data types based on tables and columns
Understanding what collections are
Using the BULK COLLECT keyword to fetch data in bulk
These are all great features of the PL/SQL language and will take your code to the...
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Singular vs Plural and Other Database Table Naming Conventions
转载:Singular vs Plural and Other Database Table Naming Conventions - Database Star
Are you wondering if you should name your SQL database tables in the singular form or plural form?
Learn what the preferred convention is and some reasoning behind it, as well as other database table naming...
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The Complete Guide to Oracle REGEXP Functions
转载:The Complete Guide to Oracle REGEXP Functions - Database Star
Are you confused by Oracle regular expressions? Want to know how to use them to get the information you need for your queries? Learn all about Oracle REGEXP functions in this article.
# What is a Regular Expression?
A regular...
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SQL Window Functions
转载:SQL Window Functions: The Ultimate Guide - Database Star
What is an SQL window function? Why should you know about it? And what can it help you with?
You may have heard of SQL window functions before, or they may be completely new to you.
Learn all about them in this guide.
# What is a Window...
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Oracle Calculate Median
# Median Define
统计学上,中位数(Median),又称中央值、中值,是一个样本、种群或概率分布中之一个数值,其可将数值集合划分为数量相等的上下两部分。对于有限的数集,可以通过把所有观察值高低排序后找出正中间的一个作为中位数。如果观察值有偶数个,则中位数不唯一,通常取最中间的两个数值的平均数作为中位数。
一个数集中最多有一半的数值小于中位数,也最多有一半的数值大于中位数。如果大于和小于中位数的数值个数均少于一半,那么数集中必有若干值等同于中位数。
# Data Set
123456789101112create table movie_ratings ( rating...
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7 Simple but Tricky JavaScript Interview Questions
转载: 7 Simple but Tricky JavaScript Interview Questions
My top stressing things in software development are:
The coding interview
A toxic manager or teammate
Not JavaScript, this , CSS, Internet Explorer, but the 2 above.
If you’re qualifying as Senior Developer whose job involves JavaScript,...
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How to Get the Screen, Window, and Web Page Sizes in JavaScript
转载:How to Get the Screen, Window, and Web Page Sizes in JavaScript
To detect whether the browser window is in landscape or portrait mode, you can compare the browser window’s width and height.
But from my experience it’s easy to get confused in the bunch of sizes: screen, window, web page...
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JavaScript Variables Lifecycle Why let Is Not Hoisted
转载:JavaScript Variables Lifecycle: Why let Is Not Hoisted
Hoisting is the process of virtually moving the variable or function definition to the beginning of the scope, usually for variable statement var and function declaration function fun() {...} .
When let (and also const and...
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