I have this SQL query: And it returns the error : “unknown column main.cname in filed list”. while the column certainly exists: seems alright. I tried using aliases but it just made it worse. I’m clueless Answer As coyeb60297 has pointed out, MySQL doesn’t do full outer joins so your q…
Tag: mysql
SELECT from table with count from another
I have 2 mysql tables I need to get all views by user, but also need to get the user role (for each view) and calculate a dynamic number of users used for every view. So, I need to get all view columns, plus the role of the user which do this request (from ViewUser), plus count of users for
How to fill missing values in aggregate-by-time function
I have function (from this question) which groups values by every 5 minutes and calculate min/avg/max: However, due to missing values, some five-minute periods are skipped, making the timeline inconsistent. How to make it so that in the absence of data for a certain period, the value of max / avg / min become…
Retrive data of last month using Python with source as MYSQL
I am getting an error while retrieving data of the last month using python. What is the best approach for the given piece of code? I am not able to get solution, What changes can I do. I am using MYSQL as my source database and Python 3.7.4 as my programming language. Since error is big, posting it in two
how to query get value without id
I want to get the value of the column regardless of the id of the table, because I want to use GROUP BY to concatenate them from the table : id_child id_master test1 test2 test3 1 1 1 1 0 2 1 1 0 0 3 1 1 0 0 4 2 1 0 0 5 2 1 0 0
How to use INSERT INTO — SELECT with new timestamp?
I’m working on a small website, that keep tracks of students information, When someone makes an update on one of the students I want to archive a copy of the previous record, I know that doing this makes a copy of the current data. But I want to include the date when the edit was made, so I tried this,
SQl query to show the most popular category in terms of sales quantity for each country and each gender in year XXXX
There are Three tables here Orders, Customers and Items. Please tell me how to solve this. I have tried few combinations but were not successful. Thanks in advance. Answer In Mysql 8 you have ROW_NUMBER to select the “best” from a PARTITION country | gender | category | oYear | total :—̵…
MySQL find first row base on multiple conditions
Suppose exists a table as follows: For each id, i want to keep the row with maximum B, if B equals, then keep the row with maximum C. So the final result is, how to realize it by SQL? Answer Maximum tasks can be solved with NOT EXISTS. You only want rows for which not exists a row with the
Convert Timestamp to MYSQL Date In Query usable in WHERE
I am working with a MYSQL database where the developer has stored the date as a timestamp instead of a ‘datetime’ field that can be queried. The following query creates an ‘AS’ field date_formatted and the output is correct. However that field cannot be used in a WHERE statement to lim…
How to update MySQL rows from 4th row to end of the result? [closed]
Closed. This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed last year. Improve this question For example, I have n rows, I need to update from the 4th row to the nth row. here n means the…