The percent sign % and underscore _ are metacharacters within SQL LIKE clauses. JDBC provides syntax to force these characters to be interpreted literally. The JDBC clause immediately following a LIKE expression allows you to specify an escape character:
In some languages, a single character consists of more than one collation unit (a 16-bit character). The escapeCharacter used in the escape clause must be a single collation unit in order to work properly.
You
can also use the escape character sequence for LIKE without using JDBC's curly
braces; see