[sql] SQL subquery with COUNT help

I have an SQL statement that works

SELECT * FROM eventsTable WHERE columnName='Business'

I want to add this as a subquery...

COUNT(Business) AS row_count

How do I do this?

Do you want to get the number of rows?

SELECT columnName, COUNT(*) AS row_count
FROM eventsTable
WHERE columnName = 'Business'
GROUP BY columnName

Assuming there is a column named business:

SELECT Business, COUNT(*) FROM eventsTable GROUP BY Business

SELECT e.*,
       cnt.colCount 
FROM eventsTable e
INNER JOIN (
           select columnName,count(columnName) as colCount
           from eventsTable e2 
          group by columnName
           ) as cnt on cnt.columnName = e.columnName
WHERE e.columnName='Business'

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