![]() Sometimes, from the database table rows, we want to fetch data having a date column with the Date data type as today, and then the query will be written as: SELECT ColumnName FROM TableName WHERE ExpiredDate = Today Let us consider accessing today’s date by implementing the built-in date functions to provide the current date in the MySQL database. The term “FunctionName” is mentioned in the above syntax of the stored program function. We can call the newly built stored program with the following MySQL query and execute the output as desired: SELECT FunctionName() ![]() On execution, the stored function terminates instantly if the RETURN query is visited.Īfter executing the properly stored program syntax above, using valid names for functions, parameters, and data types, the stored function will be created in the MySQL database. In the body block section, at least a single RETURN query statement should be mentioned, which returns the result value to the calling function. Between the BEGIN and END keyword blocks, we can write the code in this body for the stored function.But MySQL uses the NOT DETERMINISTICkeyword option by default if we do not set anyone. In a deterministic function, it also returns the identical result for similar parameters as inputs, whereas, in a non-deterministic one, it outputs different values for similar parameters as inputs. Then, we must state the DETERMINISTIC keyword to make the function either deterministic or not.With the RETURNS statement, we will specify the valid MySQL Data type for which we are creating the stored program function.All these parameters are the MySQL IN parameters by default, so we cannot state OUT, INOUT, or IN modifiers to those parameters. The stored function name followed us we need to list all the parameters we wanted to mention within the parentheses.FunctionName specifies the name we give to the stored function when using the CREATE FUNCTION keyword to name and create it.RETURN Replaceable_Stored_FunctionName // statementsĮxplaining the terms of the above syntax below: RETURNS Data_Type // Declare the datatype This is possible by the succeeding SQL command code structure firstly: DELIMITER $$ // creating stored function program Now, we can replace this MySQL CURDATE() function or CURRENT_DATE() function with MySQL Today() function to make the query statements more comprehensible. As we know CURDATE() function or CURRENT_DATE() function in MySQL provides the current date, and we also use it most of the time to retrieve the current date or time in MySQL queries. We must create your own MySQL Today() function as a stored program. It will return the number of fractional seconds you specify.To get MySQL Today() function to result in today’s date, we will use the built-in functions of the date data type. If you want to get a more accurate result, use an integer from 1 to 6 as the optional argument (as with CURRENT_TIMESTAMP). You can leave the brackets empty, which returns the date and time without fractional seconds. Unlike CURRENT_TIMESTAMP, NOW() requires brackets. ![]() Let’s see an example with NOW(): SELECT NOW() The difference is that CURRENT_TIMESTAMP is the SQL standard function, while NOW() is specific to MySQL. The NOW() function is similar to the CURRENT_TIMESTAMP function and returns the same result. This result contains a 6-digit fractional second because we put 6 as the optional argument in the CURRENT_TIMESTAMP function. This returns the date and time with six fractional seconds, like so: 12:08:56.146153 A 1 denotes only one place after the decimal, a 3 denotes three places, etc. Simply place an integer from 1 to 6 within the brackets – this determines the number of fractional seconds to include after the decimal. ![]() However, you can use brackets to specify a higher precision time. It is given as a value in the 'YYYY-MM-DD hh:mm:ss' format. the time for the machine running that instance of MySQL). The CURRENT_TIMESTAMP function in the MySQL database returns the current date and time (i.e. Here’s the result of the query: 11:13:17 Discussion: We’ll use one of two functions, CURRENT_TIMESTAMP or NOW(), to get the current date and time. You’d like to get the current date and time for a MySQL database.
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