Database.Guide – Page 380

CRC stands for Cyclic Redundancy Check. A CRC is an error-detecting code commonly used in digital networks and storage devices to detect accidental changes to raw data (although, it doesn’t necessarily guard against malicious or intentional changes).

MySQL COT() Function – Return the Cotangent of a Number in MySQL

November 19, 2019October 4, 2018 by Ian

In MySQL, the COT() function returns the cotangent of a given value.

You provide the value as an argument when calling the function.

MySQL COS() Function – Return the Cosine of a Number in MySQL

November 19, 2019October 2, 2018 by Ian

In MySQL, the COS() function returns the cosine of a given value, where the value is given in radians.

The cosine is the trigonometric function that is equal to the ratio of the side adjacent to an acute angle (in a right-angled triangle) to the hypotenuse.

MySQL ABS() Function – Return the Absolute Value of a Number

November 19, 2019October 2, 2018 by Ian

In MySQL, the ABS() function returns the absolute value of a given value.

An absolute value is the distance of a number on the number line from 0 without considering which direction from zero the number lies. Therefore, the absolute value of a number is always a non-negative value (i.e. it’s never negative).

MySQL PI() Function – Return the Value of π (pi)

November 19, 2019September 22, 2018 by Ian

In MySQL, the PI() function returns the value of π (pi). The number π is a mathematical constant approximately equal to 3.14159 (although it can also be displayed with much greater precision than this).

The PI() function displays π with a default precision of 7 (i.e. 3.141593), however MySQL uses the full double-precision value internally.

MySQL RAND() Function – Generate a Random Number in MySQL

February 14, 2020September 16, 2018 by Ian

In MySQL, the RAND() function allows you to generate a random number. Specifically, the function returns a random floating-point value v in the range 0 <= v < 1.0.

You can also influence the random number by providing a seed value as an argument.

MySQL ROUND() Function – Round a Number to a Given Number of Decimal Places

November 19, 2019August 28, 2018 by Ian

In MySQL, the ROUND() function allows you to round a number up or down to a given number of decimal places.

The way it works is, you provide the number as an argument, and you have the option of choosing how many decimal places to round the number to. If you don’t specify the number of decimal places, the result will have no decimal places.