Explicit conversion is done using cast (x as bigint) You said: As a matter of interest what is the underlying storage for Integer?
This is dictated on disk by the input format the "temporal in memory format" is dictated by the serde, an integer could be stored as "1", "<value>1</value>" , as dictated by the Input Format and Serde Storage Handler in use. On Sun, Mar 20, 2016 at 6:27 PM, Mich Talebzadeh <[email protected]> wrote: > > As a matter of interest how does how cast columns from say String to > Integer implicitly? > > For example the following shows this > > create table s(col1 String); > insert into s values("1"); > insert into s values("2"); > > Now create a target table with col1 being integer > > > create table o (col1 Int); > insert into o select * from s; > > select * from o; > +---------+--+ > | o.col1 | > +---------+--+ > | 1 | > | 2 | > +---------+--+ > > So this implicit column conversion from String to Integer happens without > intervention in the code. As a matter of interest what is the underlying > storage for Integer. In a conventional RDBMS this needs to be done through > cast (CHAR AS INT) etc? > > Thanks > > > > Dr Mich Talebzadeh > > > > LinkedIn * > https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw > <https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw>* > > > > http://talebzadehmich.wordpress.com > > >
