Data Type

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The amount column is stored as text and cannot be summed. Change it to a number type, and switch date to a real date picker.

A data type is the format agreement for one piece of information: text, number, date, or an on/off value.If the amount field is a number type, phones show a numeric keyboard and records can be summed; stored as text, it can neither compare nor total. A date type opens a date picker and enables time sorting. The type fixes the format before entry, while validation checks at submit—two things that happen in order.
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