How are lookup fields stored in a child table?

When a child table has a lookup field added, does the parent data in that field get duplicated and stored in the child table, thus enlarging the child table by the full size of the looked up data?  Or is there just some kind of "pointer" stored in the child table, which enlarges the child table to a much lesser degree?  #Relationships #tablespace​​​​ #Lookup​

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Jeffrey Pierce
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