Procedure Definitions

func_def:
      CREATE [OR REPLACE] PROCEDURE qname '(' [ paramlist] ')' routine_body
    | CREATE [OR REPLACE] PROCEDURE qname '(' [ paramlist] ')' EXTERNAL NAME external_function_name

routine_body:
      procedure_statement
    | BEGIN procedure_statement_list procedure_statement ';' END
    | BEGIN ATOMIC procedure_statement_list procedure_statement ';' END

procedure_statement:
      update_statement
    | select_statement_single_row
    | schema
    | grant
    | revoke
    | create_statement
    | drop_statement
    | alter_statement
    | declare_statement
    | set_statement
    | control_statement
    | transaction_statement

update_statement:
      delete_stmt
    | truncate_stmt
    | insert_stmt
    | update_stmt
    | merge_stmt
    | copyfrom_stmt
    | copyto_stmt

declare_statement:
      DECLARE variable_list
    | DECLARE table_def

set_statement:
      SET variable_ref '=' search_condition
    | SET variable_ref_commalist_parens '=' subquery
    | SET SESSION AUTHORIZATION opt_equal ident
    | SET session_schema opt_equal ident
    | SET session_user opt_equal ident
    | SET session_role opt_equal ident
    | SET session_timezone opt_equal LOCAL
    | SET session_timezone opt_equal literal

control_statement:
      call_procedure_statement
    | call_statement
    | while_statement
    | if_statement
    | case_statement
    | return_statement

transaction_stmt:
      { START | BEGIN } TRANSACTION transaction_mode_list
    | COMMIT opt_work opt_chain
    | ROLLBACK opt_work opt_chain opt_to_savepoint
    | SAVEPOINT ident
    | RELEASE SAVEPOINT ident
    | SET LOCAL TRANSACTION transaction_mode_list
    | SET TRANSACTION transaction_mode_list

See also system tables/views: sys.functions where type = 2, sys.args,
information_schema.routines where routine_type = 'PROCEDURE',
information_schema.parameters where function_type = 2.