MySQL length() not giving correct number of characters

Question

I have a table with 8 columns, all varchar (24, 24, 24, 5, 5, 255, 255, 255).

The three important columns are:

icd10code (varchar 24)    
icd10codedot (varchar 24)   
icd10length (varchar 5)

I wish to convert one column that looks like this - "ABCDEF" to this - "ABC.DEF".

Here is the MySQL query used, and it worked perfectly!

UPDATE icd10
 SET icd10codedot =
 CONCAT (     LEFT(icd10code, 3) ,
              "." ,
              RIGHT( icd10code, ( LENGTH(icd10code)-3 )
                    )
        );

All 91,000 rows came out nice EXCEPT there was a trailing "." at the end of those entries that only had 3 characters - like this: "ABC.". I don't want that dot at the end.

So I tried this:

UPDATE icd10 SET icd10codedot = LEFT(icd10codedot, 3) WHERE LENGTH(icd10codedot)=4;

and this:

UPDATE icd10 SET icd10codedot = LEFT(icd10code, 3) WHERE LENGTH(icd10code)=3;

and this:

UPDATE icd10 SET icd10codedot = LEFT(icd10code, 3) WHERE LENGTH(icd10code)=3;

and none of them worked (a bunch of other combinations were also run, but none worked).

So to see how things were doing in the code, I made a column called "icd10length" varchar int and did this query:

UPDATE icd10 SET icd10length = LENGTH(icd10code);

and all I got was 91,000 "7"s lined up on the right of the column.

I changed the column from INT to VARCHAR 5, and reran the query and got 91000 "7"'s lined up on the RIGHT of the column ( :-) ).

So two questions:

1. How can I get the correct length of the variable icd10code or icd10codedot into a column?

2. Do you have a slick way of clipping the last character of a string that is 4 characters long?

Thanks very much again!

PS - I tried the initial query in PHP and it crashed - timing out after 300 seconds. Found on the web that you should always do things in MySQL whenever possible.

PSS - I'm doing all of this via phpMyAdmin.

Answer 1

It seems you have empty space at the end, try using rtrim.