Retrieving Unique Values From a MySQL Column
When dealing with databases, it is often necessary to retrieve only unique values from a particular column. This can come in handy when generating reports or displaying data in a user interface.
In this specific case, the goal is to display unique dates from a table called "buy." The table contains multiple rows with duplicate dates, and the task is to ensure that only distinct dates are displayed.
To solve this problem, one can employ the DISTINCT operator in MySQL. By including DISTINCT in the SELECT statement, one can ensure that only unique values are returned. Here's an example:
<br>SELECT DISTINCT(Date) AS Date FROM buy ORDER BY Date DESC;<br>
In this query, the DISTINCT operator is applied to the Date column. This ensures that only unique dates will be returned in the results. The ORDER BY clause is added to sort the dates in descending order, allowing them to be displayed in a meaningful order.
By using the DISTINCT operator, we can effectively eliminate duplicate dates from the results. This will result in a more concise and informative display of data, meeting the requirement of displaying only unique dates.
The above is the detailed content of How to Retrieve Only Unique Dates from a MySQL Column?. For more information, please follow other related articles on the PHP Chinese website!

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