What does adding and to a search query do

Adding AND to a search query provides the search results based on conditions imposed on both side of AND.

Explanation:

AND is often used in search queries to filter the search results based on multiple conditions.

Let's illustrate the working of AND using following example.

Consider the student table shown below.

Now consider the following query is run on student table.

Select *

From Student

Where Marks > 50 AND Age >15;

Since here AND condition is used in Where clause. Therefore,  search result will include all those tuples in which the marks value is more than 50 and along with that the age value is more than 15.

Thus the result of above query will be as follows:

the today function returns a valid value without any arguments.

the today function returns the current date based on the computer's date setting and formatted as a date. today takes no parameters, but requires that you use empty parentheses