How do you add a specific number of days to a date in mysql?
IntroductionWhen working with relational databases and Structured Query Language (SQL), there may be times when you need to work with values representing specific dates or times. For instance, you may need to calculate the total hours spent on a certain activity, or perhaps you need to manipulate date or time values using mathematical operators and aggregate functions to calculate their sum or average. Show
In this tutorial, you will learn how to use dates and
times in SQL. You’ll begin by performing arithmetic and using various functions with dates and times using only the PrerequisitesTo complete this tutorial, you will need:
Note: Please note that many relational database management systems use their own unique implementations of SQL. Although the commands outlined in this tutorial will work on most RDBMSs, the exact syntax or output may differ if you test them on a system other than MySQL. To practice using date and time in this tutorial, you’ll need a database and table loaded with sample data. If you do not have one ready to insert, you can read the following Connecting to MySQL and Setting up a Sample Database section to learn how to create a database and table. This tutorial will refer to this sample database and table throughout. Connecting to MySQL and Setting up a Sample DatabaseIf your SQL database runs on a remote server, SSH into your server from your local machine:
Next, open the MySQL prompt,
replacing
Create a database named
If the database was created successfully, you’ll receive the following output:
To select the
After selecting the database, create a table within it. For this tutorial’s example, we’ll create a table that holds two runners’ results for various races they’ve run in the span of a year. This table will hold the following seven columns:
Create the table by running the
Next insert some sample data into the empty table:
Once you’ve inserted the data, you’re ready to begin practicing some arithmetic and functions with date and time in SQL. Using Arithmetic with Dates and TimesIn SQL, you can manipulate date and time values using mathematical expressions. All that’s required is the mathematical operator and the values you want to calculate. As an example, say you wanted to find one date that is a certain number of days after another. The following query takes one date value
(
As this output indicates, 17 days after As another example, say you want to calculate the total hours between two different times. You can do this by subtracting the
two times from one another. For the following query,
This output tells you that the difference between 11:00 and 3:00 is Now practice using arithmetic on the date and time information from the sample data. For the first query, calculate the total time it took the runners to
finish each race by subtracting
You’ll notice that this output in the Now, if you were only interested in each runner’s performance for longer races, such as the half and full marathons, you can query your data to retrieve that information. For this query, subtract
In this section, you performed some arithmetic on dates and times with the Using Date and Time Functions and Interval ExpressionsThere are several functions that can be used to find and manipulate date and time values in SQL. SQL functions are typically used to process or manipulate data, and the functions available depend on the SQL implementation. Most SQL implementations, however, allow you to find the current date and time by querying for the To find today’s date, for example, the syntax is short and comprised of only the
Using the same syntax, you can find the current time with the
If you prefer to query for both date and time in the output, use the
You can use date and time functions like these within arithmetic functions similar to the previous section. For example, say you want to know what the date was 11 days ago from today’s date. In this case, you could use the same syntax
structure you used previously to query the
As this output indicates, 11 days ago from the
This output shows that when you subtract
Example interval expression
For instance, to find the date five days from now, you could run the following query:
This example finds the
This is much less ambiguous than the following query, which produces similar, though not identical output:
Note that you can also subtract intervals from dates or times to find values from before the specified date value:
What units are available for you to use in
Now that you’ve learned about interval expressions and some date and time functions, continue on to practice working with the sample data you inserted in the first step. Using CAST and Aggregate Functions with Date and TimeRecall from the third example in the Using Arithmetic with Dates and Times section, when you ran the following query to subtract
Because you’re performing an operation with two columns that have different data types ( To help make this data clearer to read and interpret, you can use the The following query is identical to the previous example, but uses a
Now, let’s use a few aggregate functions in combination with the
This output shows each runner’s shortest run-time, in this case a minimum of six minutes and 30 seconds for Bolt, and seven minutes and 15 seconds for Felix. Next, find each runner’s longest run-time. You can use the same syntax as the previous query, but this time replace
This output tells us that Bolt’s longest run-time was a total of three hours, 23 minutes, and 10 seconds; and Felix was a total of four hours, two minutes, and 10 seconds. Now let’s query for some high-level information about the total hours each runner spent running. For this query, combine the
Interestingly, this output shows the interpretation for MySQL, which is actually calculating the total time as integers. If we read these results as time, Bolt’s total time breaks down as five hours, 28 minutes, and 80 seconds; and Felix’s time breaks down as seven hours, 61 minutes, and 49 seconds. As you can tell, this breakdown of time doesn’t make sense, which indicates it’s being calculated as an integer and not time. If you tried this in a different DBMS, such as PostgreSQL, for example, the same query would look slightly different:
In this case, the query in PostgreSQL interprets the values as time and calculates them as such, so that Felix’s results break down to a total of 10 hours, one minute, and 44 seconds; and Bolt’s as six hours, nine minutes, and 20 seconds. This is an example of how various DBMS implementations may interpret data values differently even if it’s using the same query and data set. ConclusionUnderstanding how to use date and time in SQL is useful when querying for specific results such as minutes, seconds, hours, days, months, years; or a combination of all of those. Additionally, there are many functions available for dates and times that make it easier to find certain values, like the current date or time. While this tutorial used only addition and subtraction arithmetic on dates and times in SQL, you can use date and time values with any mathematical expression. Learn more from our guide on mathematical expressions and aggregate functions and try them out with your date and time queries. How can I add 15 days to current date in MySQL?Use the DATE_ADD() function if you want to increase a given date in a MySQL database. In our example, we increased each start date by two days. This function takes two arguments. The first argument is the date or datetime you want to change.
How add days to now in MySQL?INSERT INTO yourTableName VALUES(DATE_ADD(now(),interval n day)); In the above syntax, you can use curdate() instead of now(). The curdate() will store only date while now() will store both date and time.
How can I increase 1 day date in SQL?Learn MySQL from scratch for Data Science and Analytics
We can add 1 day to the date with the help of DATE_ADD() function.
What is the length value for date in MySQL?MySQL retrieves and displays DATE values in ' YYYY-MM-DD ' format. The supported range is '1000-01-01' to '9999-12-31' .
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