SQL placeholder in WHERE IN, inserted rows do not work

Question

As part of my assignments, I need to write SQL queries to connect to our PI database. To generate a request, I need to pass an array of tags (essentially primary keys), but they must be inserted as strings.

Since this will be a modular query and used for multiple tags, a placeholder is used.

The query is based on using the WHERE IN statement where the placeholder is located, as shown below:

SELECT SUM(value * 5/1000) as "Hourly Flow [kL]" 
  FROM piarchive..pitotal 
 WHERE tag IN (?) 
   AND time between ? and ? 
   AND timestep = '1d' 
   AND calcbasis = 'Eventweighted' 
   AND value <> ''

The problem is the format in which tags should be passed as. If I add them directly to the request (for testing), they go in the format (these are example numbers): '000000012','00000032','005050236','4560236' and the request looks like this:

SELECT SUM(value * 5/1000) as "Hourly Flow [kL]" 
  FROM piarchive..pitotal 
 WHERE tag IN ('000000012','00000032','005050236','4560236') 
   AND time between ? and ? 
   AND timestep = '1d' 
   AND calcbasis = 'Eventweighted' 
   AND value <> '' 

... which is working.

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Answer 1

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select *
from pitotal
where tag IN (SELECT tag from pipoint WHERE INSTR(?, tag) <> 0) and time between 'y' and 't'

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Answer 2

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Answer 3

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WHERE tag IN (?,?,?,?,?)

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WHERE tag IN (7,3,1,8,9)

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WHERE tag IN (7,7,1,7,9)

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