![]() Use it with an ORDER BY clause to sort the rows in ascending order by date. STR_TO_DATE(CONCAT(exam_year, ' ', exam_month, ' ', exam_day), '%Y %M %d') %Y stands for year, %M stands for month (its full name, not a number), and %d stands for day. The second argument of this function is the date format. Then, you need to convert this string to a date using the STR_TO_DATE(date_string, '%Y %M %d') function. Since you'd like to get a string in the ' Year Month Day' format, the arguments are exam_year, exam_month, exam_day, and the spaces between them. You don't need to cast numbers to strings. The CONCAT() function combines all the arguments into one string. But first, you need to create a string using the CONCAT() function:ĬONCAT(exam_year, ' ', exam_month, ' ', exam_day) If you have a date stored as a string in the ' Year Month Day' format, you can cast it to a date using STR_TO_DATE(date_string, '%Y %M %d'). ![]() To do this, use the STR_TO_DATE() function. This release of PMM starts the series of enhancements that will improve how you work with Services and Nodes in PMM. It is an open source database monitoring, management, and observability solution for MySQL, PostgreSQL, and MongoDB. To sort by date, create date values from the year, the month, and the day values. On May 2, 2023, Percona Monitoring and Management 2.37 (PMM) was released. The result looks like this (the rows are sorted in ascending order by exam_year, exam_month, and exam_date): subject ORDER BY STR_TO_DATE(CONCAT(exam_year, ' ', exam_month, ' ', exam_day), '%Y %M %d') The months are given in names, not in numbers. The exam table has the following columns: subject, exam_year, exam_month, and exam_day. Return the last error description for the most recent function call, if any: result looks like this (the rows are sorted in ascending order by exam_date): subject The exam table has two columns, subject and exam_date. A simple and efficient way to get the largest record in a group.You want to sort the rows by date. Running the query above will get you the following results table: ID Gallery Submitted DescriptionĪnd there you have it. summarizes the corresponding operations for DB2, MySQL, Oracle. This may be a simple query, but I'm having trouble getting my head around a reliable. ![]() If a customer purchased from supplier 'A' last month, but their most recent purchase was, say, yesterday from supplier 'B', then I don't want them included in the result. ON (i1.Gallery = i2.Gallery AND i1.Submitted < i2.Submitted) These are often queries for the most recent or the best entries of a result set. I need to run a query to select those whose most recent purchase was from supplier 'A'. ![]() So in my query example below I join the table back to itself and find the largest submitted time in a group by using a left join, which will allow us to identify the largest records by finding the rows where the left join failed to join to anything that was bigger than itself. MS SQL: SELECT TOP 1 FROM tablename ORDER BY primaryidfield DESC MySQL: SELECT FROM tablename ORDER BY primaryidfield DESC LIMIT 0,1 More code articles Paul Silver. Now normal Group By queries can get you the Gallery and Submitted field, unfortunately you cannot also retrieve the ID and description with these when using a group by. Just replace 'tablename' with the name of your table, and 'primaryidfield' with the name of your primary ID field and it will give you the most recent record. Now in our example we want to find the last image submitted for each gallery. Table: Images ID Gallery Submitted Descriptionġ Cats 12-01-2012 00:00:12 This is my pretty kittyģ Dogs 12-04-2012 05:00:12 Who let the dogs outĥ Birds 12-06-2012 01:00:12 Polly Wants a Cracker Prerequisites: Access to run SELECT queries on MySQL Goal: Selecting the top value for by group (such as highest date or largest value) ![]()
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