Most likely, at least some of your database tables have some kind of string columns, whether they are
CHAR, VARCHAR2, CLOB, or one of the equivalent multibyte versions. Once you have these columns in your tables, you generally have to do more than just display or capture the values in those columns. Thus, the focus of the recipes in this chapter is on searching, concatenating, and splitting string values in database columns.
Oracle has many built-in functions to search and manipulate strings. The
INSTR function searches for a specified string within a second string. You can start the search anywhere within the second string, and you can also search for a specific occurrence of the first string as well.
To perform one-to-one substitutions ...