UndefRefError - Trying access variable inside for

General Usage
,
1

I’m using DBInterface and MySQL to interact with my MySQL database, but my function is stucking into a strange error.

This function below works well, but is slow and inefficient:

function insertNewDebDataIntoDatabase(df::DataFrame)
    conn::DBInterface.Connection = getConnection()
    
    for row in eachrow(df)
        query = DBInterface.prepare(
            conn,
            "INSERT INTO DebSchedule ..."
        )
        DBInterface.execute(
            query, [
            row[:RptDt],...])
        DBInterface.close!(query)
    end

end

But this below doesn’t work:

function insertNewDebDataIntoDatabase(df::DataFrame)
    conn::DBInterface.Connection = getConnection()
    query = DBInterface.prepare(
            conn,
            "INSERT INTO DebSchedule ..."
        )
    
    for row in eachrow(df)
        
        DBInterface.execute(
            query, [
            row[:RptDt],...])
    end
    DBInterface.close!(query)

end

This throws ERROR: UndefRefError: access to undefined reference.
I don’t see why the difference between them could be a problem.