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How is a generated column stored in PostgreSQL?
A virtual generated column occupies no storage and is computed when it is read. Thus, a virtual generated column is similar to a view and a stored generated column is similar to a materialized view (except that it is always updated automatically). PostgreSQL currently implements only stored generated columns.
How is a view created in a PostgreSQL query?
The view is not physically materialized. Instead, the query is run every time the view is referenced in a query. CREATE OR REPLACE VIEW is similar, but if a view of the same name already exists, it is replaced.
How is the default value set in PostgreSQL?
These forms set or remove the default value for a column. A default value associated with a view column is inserted into INSERT statements on the view before the view’s ON INSERT rule is applied, if the INSERT does not specify a value for the column. The user name of the new owner of the view.
What does alter view mean in PostgreSQL documentation?
ALTER VIEW is a PostgreSQL extension of the SQL standard.
How can I store latitude and longitude without PostGIS?
The simplest solution without PostGIS would be to store lat/long as two number columns. numeric for exact precision. double precision or even just real if you don’t need the precision. I see no reason why the data type point shouldn’t work as well.
How many bytes are in a column in PostgreSQL?
Occupies 16 bytes: 2 float8 numbers internally. Or make it two columns of type float (= float8 or double precision ). 8 bytes each. Or real (= float4) if additional precision is not needed. 4 bytes each.
Can a generated column be part of a foreign table?
A generated column cannot have a column default or an identity definition. A generated column cannot be part of a partition key. Foreign tables can have generated columns. See CREATE FOREIGN TABLE for details.
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