SQL code writing style

 It is important to adopt a consistent style to write SQL code. The readability is improved and further revisions are easier 

I recommend capital letters for reserved words and lowercase for schema names, table names, column names, bind variables, procedures and function names.

e.g.

SELECT col1, col2

  FROM owner.table

WHERE col3 = :bind1

   AND SUBSTR(col4,1,1) = ‘A’