Just got a little question when a column got the Datatype Number(6,3) will this work? <pre class="prettyprint"><code>1234 1234.23 12345 123456 </code></pre> btw google didnt help me :/

No, this won't. <code>NUMBER(6, 3)</code> accepts <code>6</code> digits at all with <code>3</code> being after the decimal period. This gives us only <code>3</code> digits possible before the period, and, hence, maximal value possible to store is <code>999.999</code>