SQL functions are built into Oracle Database and are available for use in various appropriate SQL statements. Do not confuse SQL functions with user-defined functions written in PL/SQL. If you call a SQL function with an argument of a datatype other than the datatype expected by the SQL function, then Oracle attempts to convert the argument to the expected datatype before performing the SQL function. If you call a SQL function with a null argument, then the SQL function automatically returns null.
Marching. Marching refers to the organized, uniformed, steady and rhythmic walking forward, usually associated with military troops. Marching is often performed to march music, and often associated with military parades. Marching is part of basic training in the military in most countries. In most cases, marching uses a system of drill commands. Learning to march by obeying commands is considered a form of discipline.
Firefighters marching in a parade. Synchronization is the coordination of events to operate a system in unison. The familiar conductor of an orchestra serves to keep the orchestra in time. Systems operating with all their parts in synchrony are said to be synchronous or in sync; those which are not are asynchronous.