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Foreign key constraints: When to use ON UPDATE and ON DELETE
... interesting thing to do with that on an update, but I may be wrong.
And now on the ON DELETE side:
ON DELETE RESTRICT : the default : if you try to delete a company_id Id in table COMPANY the engine will reject the operation if one USER at least links on this company, can save your life.
ON DEL...
Inline SVG in CSS
...the same jsfiddle example in base64: http://jsfiddle.net/vPA9z/3/
The CSS now looks like this:
body { background-image:
url("data:image/svg+xml;base64,PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHdpZHRoPScxMCcgaGVpZ2h0PScxMCc+PGxpbmVhckdyYWRpZW50IGlkPSdncmFkaWVudCc+PHN0b3Agb2Zmc2V0P...
Can someone explain mappedBy in JPA and Hibernate?
...urce of truth when it comes to managing a one-to-many table relationship.
Now, if you take a bidirectional entity relationship that maps on the one-to-many table relationship we saw previously:
If you take a look at the diagram above, you can see that there are two ways to manage this relationsh...
Casting a variable using a Type variable
...pe intType = typeof(Int32);
object value1 = 1000.1;
// Variable value2 is now an int with a value of 1000, the compiler
// knows the exact type, it is safe to use and you will have autocomplete
int value2 = Convert.ChangeType(value1, intType);
// Variable value3 is now an int with a value of 1000...
python-pandas and databases like mysql
...
frame_query is now deprecated. Now use pd.read_sql(query, db) instead.
– Robert Smith
Apr 24 '15 at 22:43
add a com...
What is the difference between URI, URL and URN? [duplicate]
...rce either by location, or a name, or both. A URI has two specializations known as URL and URN.
A Uniform Resource Locator (URL) is a subset of the Uniform Resource Identifier (URI) that specifies where an identified resource is available and the mechanism for retrieving it. A URL defines how the r...
How does C compute sin() and other math functions?
...s code uses some numerical hacks I've never seen before, though for all I know they might be well-known among floating-point experts. Sometimes a few lines of code would take several paragraphs to explain. For example, these two lines
double t = (x * hpinv + toint);
double xn = t - toint;
are use...
How to make an Android Spinner with initial text “Select One”?
...e from above into your project, e.g. into package com.example.customviews. Now in your layout xml, instead of <Spinner ...> use <com.example.customviews.NoDefaultSpinner ...> The rest of the code can stay the same. Don't forget to add the android:prompt attribute to the <com.example.c...
Is there any way to do HTTP PUT in python
...
This answer was brilliant when it was written, but nowadays it's a lot easier to use the 'requests' package instead, see John Carter's answer. 'Requests' is in no way a toy - it is extremely capable.
– Jonathan Hartley
Feb 8 '12 at 18:15...
How do I prevent node.js from crashing? try-catch doesn't work
...sn't work either since everything is done asynchronously. I would like to know what does everyone else do in their production servers.
...