Да пробелы
не
важны Можно став-
ить
как угодно
Но лучше следовать какому-либо из популярных соглашений, тогда другим ваш код будет легче читать.Unlike the double-quoted and heredoc syntaxes, variables and escape sequences for special characters will not be expanded when they occur in single quoted strings.
When used with a subquery, the word IN is an alias for = ANY. Thus, these two statements are the same:
SELECT s1 FROM t1 WHERE s1 = ANY (SELECT s1 FROM t2);
SELECT s1 FROM t1 WHERE s1 IN (SELECT s1 FROM t2);