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I have a resultset from a SELECT query, based on a certain ORDER BY condition, and I’m trying to check the integrity of the order in which the resultset is rendered. First, I’m specifying a LIMIT, on the basis of which, the resultset size is limited. Then, I’m selecting a random PK value from the resultset, get a particular row and use the comparison operator on that row value(s), for the next SELECT. Something like this(Let’s suppose a is the random row from above):

SELECT * FROM tbl where tbl_columnX > a.fieldX and tbl_columnY > a.fieldY
ORDER BY certain fields

Basically, what I’m trying to do here, is to ensure that for a resultset (R) of certain order, when choosing a random PK value, and issuing a SELECT statement with comparison operator(s) on that PK based row value(s), the resulting set(S) contains the rows that are in R, after/before the PK, depending whether the order is ascending or descending.

It is basically working, except for a few cases where the next row(s) after the PK based row, have the same value(s) as the PK based row, in a few column(s). For example, these are the last few rows, from the resultset R:

ID(varchar)     VALUE(varchar)  DESC1(text)     DESC2(text)     NAME(text)
-------------   -------------   -------------   -------------   -------------
62E212AF            C09A        F/T/K              AH            AN
CAFFA217            C09AA       F/T/K 2            Ah            An
D90222CC            C09BA       F/T/K 2d           Ahod          Anod

Now, if I try to get a new resultset(S) after the ID 62E212AF, it skips the ID CAFFA217, and the first ID in the resultset is D90222CC. The similar pattern is repeated in a few other places. This is how I’m doing the order by, in this particular case:

order by 
  NAME asc,
  VALUE asc,      
  DESC1 asc, 
  DESC2 asc, 
  ID asc

I’d really appreciate some help with this.

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All sorting are alphanumeric, and follow the ascii code that means

1 decimal representation 49
N decimal representation 78 
n decimal representation 110  

1 comes before N and that before n and so on, so far as i can tell it is sorting correctly.

This link shows how you can sort the text "correctly"

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