What are those SET TERM statements?

SET TERM is used by isql, FlameRobin and some other tools to change the statement terminator (TERM is short for Terminator). It is neccessary for triggers, stored procedures and execute block statements.

The reason is that the default statement terminator is semi colon (;). However, procedures and triggers contain multiple statements within, so the statement parser would stop there. Consider this example:

create procedure p1
as
begin
insert into t1 values(10);
end;

The parser would stop right after (10) and it would yield an incomplete statement. With SET TERM we change the terminator to something else, preferably a character (or characters) never used anywhere in the procedure or trigger body:

SET TERM ^ ;
create procedure p1
as
begin
insert into t1 values(10);
end^

Notice how we terminate the statement with ^ and semicolon is completely ignored.

It is a common practice to set the terminator back to semicolon after statement, to prevent problems with subsequent statements.

SET TERM ; ^

When parser parses that, it reads just "SET TERM ;" as ^ is a terminator and not included in the statement. So it's set back to semi-colon.