A generated column or a computed column is to columns what a view is to a table. PostgreSQL uses the term ‘Generated’ columns for Computed columns. The value of the column is always computed or generated from other columns in the table. A generated column can either be virtual or stored. The values for virtual columns are computed on the fly during query time and they don’t take storage space. The values for stored columns are pre-computed and stored as part of table data.
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