code: public boolean looksLikeFunctionCall(String value, Database database) {
          // TODO: SYSIBM looks DB2-specific, we should move that out of AbstractSqlGenerator into a DB2-specific class.
          return value.startsWith("\"SYSIBM\"") || value.startsWith("to_date(") ||
              value.equalsIgnoreCase(database.getCurrentDateTimeFunction());
      }
docs: Tries to find out if a given value (part a database-specific SQL statement) is just a simple literal
  (e.g. 'Jones', 149.99 or false) or if it is a call to a function within the database (e.g.
  TO_DATE('28.12.2017', 'dd.mm.yyyy') in Oracle DB).
  This method is often used to determine if we need to quote literals which are Strings, e.g. if we determine
  "Dr. Jones" to be a literal, then we generate
  <pre><code>{@code INSERT INTO customers(last_name) VALUES('Dr. Jones')}</code></pre>
  but if the value is a function call, we may not quote it, e.g. for "TO_DATE('28.12.2017', 'dd.mm.yyyy')", we
  need to generate (note the absence of the apostrophes!):
  <pre><code>{@code INSERT INTO bookings(booking_date) VALUES (TO_DATE('28.12.2017', 'dd.mm.yyyy'))}</code></pre>
  @param value The string to test
  @param database the database object to test against
  @return true if value looks like a function call, false if it looks like a literal.