====== getCommentSql ======
~~NOTOC~~
<WRAP info>Note that this function is currently only supported on Oracle databases</WRAP>
<WRAP right box>
== Syntax ==
  string getCommentSql(
    string $tableName,
    string $columnName
    )
</WRAP>
===== Description =====
The method ''getCommentSql()'' returns a string containing the SQL necessary to read the column comments from a table, if the database supports it. 


----------------------------------
===== Usage =====
<code php>
/*
* On an Oracle Database
*/
$dict = newDataDictionary($db);
$s = $dict->getCommentSql('mytable','mycolumn');
print $s;
/*
* Prints: SELECT comments 
            FROM USER_COL_COMMENTS 
           WHERE TABLE_NAME='mytable' 
            AND COLUMN_NAME='mycolumn'
*/
</code>
===== Notes =====
  * Support for this method is limited
  * Special rights may be required to execute the returned SQL
  * If not supported, the method returns false