sql server - How do I find out if a column is required or nullable using a SQL statement? -

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i need know if it's possible know if column "required" or "nullable". can't find information this. there stored procedure let's me know if column required field ?

oracle

select nullable user_tab_columns table_name = 'tablename'     , column_name = 'columnname';

sql-server

select is_nullable  sys.columns  object_id = object_id('tablename')      , name = 'columnname';

mysql

select is_nullable information_schema.columns table_name = 'tablename'     , column_name = 'columnname';

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