Combining IF with AVG in mySQL

I'd like to calculate the average of a column based on an if condition, but I'm getting stuck because, if a value is within a certain range, I'd like to set it to something else for the purposes of calculating the average.

Basically, I've tried variations of the following:

SELECT avg(IF(CAST(value AS SIGNED)<550, value, 100)) AS output...

In other words, I want to include only the values that are less than 550 as part of the average, otherwise return 100 for that cell as part of the average. So if I had the following values:

150, 200, 600, 650

then the query would calculate the average of these values:

100, 100, 600, 650.

Is there any way that this can be achieved? Aside from variations of the query above which don't seem to work, I've tried using an intermediate step that creates a new column of the actual values that need to be 开发者_JAVA技巧entered into the average, but this seems to be making the query much slower to execute.

Thanks!

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Just turn the IF around...,

SELECT AVG(IF(CAST(value AS SIGNED) < 550, 100, value)) AS output...

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AVG(CASE WHEN value < 550 THEN 100 ELSE value END)

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select avg(case when value < 550 then 100 else value end) as output...