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SQL ON DELETE CASCADE, Which Way Does the Deletion Occur?
...ould restructure your schema into this,
CREATE TABLE Categories
(
Code CHAR(4) NOT NULL PRIMARY KEY,
CategoryName VARCHAR(63) NOT NULL UNIQUE
);
CREATE TABLE Courses
(
CourseID INT NOT NULL PRIMARY KEY,
BookID INT NOT NULL,
CatCode CHAR(4) NOT NULL,
CourseNum CHAR(3) NOT NULL,
Cour...
SQL select only rows with max value on a column [duplicate]
...e).
The gist of the thing is that you create a single synthetic column by string concatenating/packing the primary comparison field along with the data you want. In this way, you can force SQL's MAX() aggregate function to return all of the data (because it has been packed into a single column). ...
How to check if my string is equal to null?
I want to perform some action ONLY IF my string has a meaningful value. So, I tried this.
27 Answers
...
How do I extract text that lies between parentheses (round brackets)?
I have a string User name (sales) and I want to extract the text between the brackets, how would I do this?
16 Answers
...
How can I make my custom objects Parcelable?
...plementation.
public class Student implements Parcelable{
private String id;
private String name;
private String grade;
// Constructor
public Student(String id, String name, String grade){
this.id = id;
this.name = name;
t...
Python truncate a long string
How does one truncate a string to 75 characters in Python?
17 Answers
17
...
How can I pass data from Flask to JavaScript in a template?
...ask provides a Jinja filter for this: tojson dumps the structure to a JSON string and marks it safe so that Jinja does not autoescape it.
<html>
<head>
<script>
var myGeocode = {{ geocode|tojson }};
</script>
</head>
<body>
<p>Hello ...
The static keyword and its various uses in C++
...tic, but can be addressed from the class as well as an instance (like std::string::npos). [Note: you can declare static members in a class, but they should usually still be defined in a translation unit (cpp file), and as such, there's only one per class]
locations as code:
static std::string name...
Why I cannot cout a string?
Why I cannot cout string like this:
7 Answers
7
...
What does the ??!??! operator do in C?
...essing, so there were some legit Fortran character sequences (in a literal string, IIRC) that were misinterpreted as C trigraphs, leading to some interesting bugs!
– Phil Perry
Apr 11 '14 at 18:25
...