PL/SQL Basics

Left Trim(Leading Spaces), Right Trim(Trailing Spaces) & Removing Extra Middle Spaces

Function for Left Trim;

function LTrimSpaces (OrgStr)

{

var Pattern = /^\s*/; //Regular Expression

Lag() function

If we had an orders table that contained the following data:

ORDER_DATEPRODUCT_IDQTY25/09/200710002026/09/200720001527/09/20071000828/09/200720001229/09/20072000230/09/200710004

Difference betweeen rank and dense_rank

Partition is made over dept_no and ordered by salary for both rank and dense_rank. They both make the same job except the numeric ranking. The same number is assigned for records with the same order value in both of them. At dense_rank, the numeric assignment…