使用PHP将MySQL查询存储在另一个表中

Question

This is my MySQL table feedback .

I want to calculate average of every column and store the result to table average as below structure using a PHP file.

I am using query SELECT AVG (waiting) FROM feedback to calculate average of waiting column. But I do not have any idea of how to put this query result to another table as the above structure.

When using query INSERT INTO average (average) SELECT AVG (waiting) FROM feedback **it only updating the average column.

Please help me with a sample code.

Thanks

Answer 1

If understand you correctly you can do it like this

INSERT INTO average (data, average)
SELECT 'waiting',      AVG (waiting)      FROM feedback UNION ALL
SELECT 'consultation', AVG (consultation) FROM feedback UNION ALL
SELECT 'preoperative', AVG (preoperative) FROM feedback 

Sample output:

|         DATA | AVERAGE |
--------------------------
|      waiting |       3 |
| consultation |       2 |
| preoperative |       3 |

Here is SQLFiddle demo

---

Now if you don't have lots of data in feedback table you can ditch average table and create a view with the same way. As a result instead of maintaining a table of averages they will be calculated on the fly when you select from it

CREATE VIEW average AS 
SELECT 'waiting',   ROUND(AVG (waiting)) average FROM feedback UNION ALL
SELECT 'consultation', ROUND(AVG (consultation)) FROM feedback UNION ALL
SELECT 'preoperative', ROUND(AVG (preoperative)) FROM feedback

And use it

SELECT * FROM average

Here is SQLFiddle demo

Answer 2

You can grab the result from the average of each column and then INSERT that into a separate database.

What you are doing now inserts it into the same column in the same database, not a different one, which is why it's just updating that column and not a different one.

Example of an INSERT query:

$query = "INSERT INTO tableName (columnName) VALUES ($averageOfColumn)";

Replace 'tableName' with the name of the new table you are connecting to.

Replace 'columnName' with the name of the column in the other database you are using.

Replace '$averageOfColumn' with your variable for the average of the waiting column.

Does this help?

Answer 3

To get average values for those three columns:

SELECT AVG(waiting),AVG(consultation),AVG(preoperative) FROM feedback;

To insert to average table, if column names are the same:

INSERT INTO average(waiting,consultation,preoperative) 
SELECT AVG(waiting),AVG(consultation),AVG(preoperative) FROM feedback