1 Reply Latest reply: May 8, 2012 2:54 AM by Bin Xue RSS

Check if a table is already loaded

Bin Xue

Hi,

 

    I would like to check if a table exist before dropping this table. I used this function

 

          if noOfRows('mytable')>0 then

          drop table mytable; 

          endif

 

   However, later i found that if a table has been created but contains no data. noOfRows function also return a number which is less or equals to zero. The scenario is as below:

 

mytable:

load *

from mytable;

inner join

load * from

anothertable;

 

The above scenario creates mytable and makes it empty by a inner join.

 

This causes my table not being dropped. Could anyone tell me if there is another way of checking the existence of a table?

  • Check if a table is already loaded
    Bin Xue

    Hi in case anybody facing the same problem. I've already found a solution. I check the output of noOfRows('table') under debug. If a table does not exist, it returns null, else it returns the number of rows in a table. So in order to check whether a table exists of not. We should use

     

    if noOfRows('table') <>null then

    ...

    endif