Inserting random numbers into MySQL database

　　

We often encounter the problem of using random numbers, and here is a way to solve a random number.

When constructing the test data, we need to insert random data into the test table. The method of constructing the test data is as follows, only the update example illustrates

Step 1: The SQL function for the random number is rand (), and Rand () generates a decimal between 0-1.

　　

Step 2: Put rand () *10

Step 3: Use cast for type conversion

The use of cast is as follows:

Cast (value as type)

Binary, with binary prefix effect: binary

Character type, with parameters: CHAR ()

Date: Date

Time:

DateTime Date/Time type

Floating point number: DECIMAL

Integer: Signed

unsigned integer: UNSIGNED

SELECT CAST (rand () *10 as signed) as RAND

Step 4: Run the SQL statement

UPDATE Storm_effect_info S SET

S.FHTP = (SELECT CAST (rand () *10 as signed) as RAND) WHERE s.id = 13

Inserting random numbers into MySQL database