### RAND
```sql
RAND()
```
####  Description
`RAND()` function is a non-deterministic random number generation function that can return a random floating-point number in the range [0, 1), with a uniform distribution. This function has a wide range of applications in various random sampling, simulation, and probability calculation scenarios.

#### Return Type
This function returns a value of type `DOUBLE`.

#### Usage Example
1. Generate a random number:
```sql
SELECT RAND(); -- Returns a random floating-point number in the range [0, 1)
```
Result Example:
   ```
   0.53298387155464
   ```
2. Generate a random number for each row in a table:
   ```sql
   SELECT id, RAND() AS random_number FROM users;
   ```
Result Example:
   ```
   1, 0.3245897911074116
   2, 0.6547382678236785
   3, 0.12345678903485962
   ```
3. Use with other numerical functions to generate a random number within a specified range:
```sql
SELECT (RAND() * 100) AS random_value BETWEEN 0 AND 100; -- Generate a random number between 0 and 100
```
Result Example:
   ```
   67.39123456
   ```
4. Used for randomly selecting records:
```sql
SELECT * FROM products ORDER BY RAND() LIMIT 1; -- Randomly select a product record
```
Result Example:
   ```
   id: 3,
   name: 'Randomly Selected Product',
   price: 19.99
   ```
#### Notes
- The `RAND()` function generates a new random number each time it is called.
- If you need repeatable random results, you can use `RAND(seed)`, where `seed` is an integer used to initialize the random number generator's seed. This way, the sequence of random numbers generated can remain consistent across multiple queries. For example:
```sql
SELECT RAND(1); -- Initialize the random number generator using seed 1
```
- In some database management systems, the `RAND()` function may have different behaviors or limitations. Please refer to the relevant documentation for the specific system.