Code prompts you that the parameters provided by froeach are invalid. You can var_dump() to see if the data after your query is correct, and then use foreach....
replyAfter you complete query($sql), you will return an array, and then you can use foreach to traverse the data. First, you must first determine the returned array, right? var_dump prints out the data and takes a look.
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Note the spaces in line 25
select * from study
Code prompts you that the parameters provided by froeach are invalid. You can var_dump() to see if the data after your query is correct, and then use foreach....