I have a set of decimal values, but I need to remove the values after the decimal if they are zero.
17.00
23.50
100.00
512.79
become
17
23.50
100
512.79
Currently, I convert to a string and replace out the trailing .00 - Is there a better method?
REPLACE(CAST(amount as varchar(15)), '.00', '')
This sounds like it is purely a data presentation problem. As such you should let the receiving application or reporting software take care of the formatting.
You could try converting the .00s to datatype int. That would truncate the decimals. However, as all the values appear in one column they will have to have the same type. Making everything an int would ruin your rows with actual decimal places.
As a SQL solution to a presentation problem, I think what you have is OK.
I would advice you to compare the raw decimal value with itself floored. Example code:
declare
#Val1 decimal(9,2) = 17.00,
#Val2 decimal(9,2) = 23.50;
select
case when FLOOR ( #Val1 ) = #Val1
then cast( cast(#Val1 as int) as varchar)
else cast(#Val1 as varchar) end,
case when FLOOR ( #Val2 ) = #Val2
then cast( cast(#Val2 as int) as varchar)
else cast(#Val2 as varchar) end
-------------
17 | 23.50
Related
In MSSQL STR returns character data converted from numeric data. The character data is right-justified, with a specified length and decimal precision. SELECT STR(123.45, 6, 1) return ' 123.5' (not '123.5') in MSSQL. Also, SELECT STR(123.45, 2, 2) return '**' in MSSQL.
There is no direct corresponding Postgres function. You have a couple things going on: rounding at variable length, padding the result and result length validation. But easy enough to create your own SQL function: (see demo)
create or replace
function str(value_in numeric
,length_in integer default 7
,dec_len_in integer default 2
)
returns text
language sql
as $$
select case when length(val) > length_in
then rpad('*',length_in,'*') -- or just '**'
else lpad(val,length_in,'#') -- for demo using #, for real use ' '
end
from (select round(value_in, dec_len_in )::text) sq(val)
$$;
In Postgresql, I need to take an ASCII string like CNR39XL and turn it into a number like 21317392311 (ASCII values - 65, but digits left as is). This is to take some logic in our software and push it down into the databse level. I’m partway there with this:
ourdb=> SELECT CASE
ourdb-> WHEN ASCII(c) < 65 THEN c::integer
ourdb-> ELSE ASCII(c)-65
ourdb-> END
ourdb-> FROM regexp_split_to_table('CNR39XL','') s(c);
case
------
2
13
17
3
9
23
11
(7 rows)
However, I can't figure out how to take that final set of numbers and convert it into the string. What am I looking for?
Use string_agg
SELECT CAST(
string_agg(
CAST (CASE ... END AS text),
''
)
AS numeric)
FROM ...
I have 2 varchar(64) values that are decimals in this case (say COLUMN1 and COLUMN2, both varchars, both decimal numbers(money)). I need to create a where clause where I say this:
COLUMN1 < COLUMN2
I believe I have to convert these 2 varchar columns to a different data types to compare them like that, but I'm not sure how to go about that. I tried a straight forward CAST:
CAST(COLUMN1 AS DECIMAL(9,2)) < CAST(COLUMN2 AS DECIMAL(9,2))
But I had to know that would be too easy. Any help is appreciated. Thanks!
You can create a UDF like this to check which values can't be cast to DECIMAL
CREATE OR REPLACE FUNCTION IS_DECIMAL(i VARCHAR(64)) RETURNS INTEGER
CONTAINS SQL
--ALLOW PARALLEL -- can use this on Db2 11.5 or above
NO EXTERNAL ACTION
DETERMINISTIC
BEGIN
DECLARE NOT_VALID CONDITION FOR SQLSTATE '22018';
DECLARE EXIT HANDLER FOR NOT_VALID RETURN 0;
RETURN CASE WHEN CAST(i AS DECIMAL(31,8)) IS NOT NULL THEN 1 END;
END
For example
CREATE TABLE S ( C VARCHAR(32) );
INSERT INTO S VALUES ( ' 123.45 '),('-00.12'),('£546'),('12,456.88');
SELECT C FROM S WHERE IS_DECIMAL(c) = 0;
would return
C
---------
£546
12,456.88
It really is that easy...this works fine...
select cast('10.15' as decimal(9,2)) - 1
from sysibm.sysdummy1;
You've got something besides a valid numerical character in your data..
And it's something besides leading or trailing whitespace...
Try the following...
select *
from table
where translate(column1, ' ','0123456789.')
<> ' '
or translate(column2, ' ','0123456789.')
<> ' '
That will show you the rows with alpha characters...
If the above does't return anything, then you've probably got a string with double decimal points or something...
You could use a regex to find those.
There is a built-in ability to do this without UDFs.
The xmlcast function below does "safe" casting between (var)char and decfloat (you may use as double or as decimal(X, Y) instead, if you want). It returns NULL if it's impossible to cast.
You may use such an expression twice in the WHERE clause.
SELECT
S
, xmlcast(xmlquery('if ($v castable as xs:decimal) then xs:decimal($v) else ()' passing S as "v") as decfloat) D
FROM (VALUES ( ' 123.45 '),('-00.12'),('£546'),('12,456.88')) T (S);
|S |D |
|---------|------------------------------------------|
| 123.45 |123.45 |
|-00.12 |-0.12 |
|£546 | |
|12,456.88| |
I have a table like this:
amount type app owe
1 a 10 10
2 a 8 -2
3 a 20 12
4 i 30 10
5 a 40 10
owe is:
(type == 'a')?app - sum(owe) where amount < (amount for current row):max(app-sum(owe)where amount<(amount for current row),0)
So I'd need a window function on the column that the window function is on. There are these partition on rows between rows unlimited preceding and prior row, but it has to be on a different column, not the column I'm summing. Is there a way to reference the same column the window function is on
I tried an alias
case
when type = a
then app - sum(owe)over(ROWS BETWEEN UNBOUNDED PRECEDING AND 1 preceding) as owe
else
greatest(0,app - sum(owe)over(ROWS BETWEEN UNBOUNDED PRECEDING AND 1 preceding))
end as owe
But since owe doesn't exist when I made it, I get:
owe doesn't exist.
Is there some other way?
You cannot do that with window functions. Your only chance using SQL is a recursive CTE:
WITH RECURSIVE tab_owe AS (
SELECT amount, type, app,
CASE WHEN type = 'a'
THEN app
ELSE GREATEST(app, 0)
END AS owe
FROM tab
ORDER BY amount LIMIT 1
UNION ALL
SELECT t.amount, t.type, t.app,
CASE WHEN t.type = 'a'
THEN t.app - sum(tab_owe.owe)
ELSE GREATEST(t.app - sum(tab_owe.owe), 0)
END AS owe
FROM (SELECT amount, type, app
FROM tab
WHERE amount > (SELECT max(amount) FROM tab_owe)
ORDER BY amount
LIMIT 1) AS t
CROSS JOIN tab_owe
GROUP BY t.amount, t.type, t.app
)
SELECT amount, type, app, owe
FROM tab_owe;
(untested)
This would be much easier to write in procedural code, sou consider using a table function.
This is what I came up with. Of course, I'm not a real programmer, so I'm sure there's a smarter way:
insert into mort (amount, "type", app)
values
(1,'a',10),
(2,'a',8),
(3,'a',20),
(4,'i',30),
(5,'a',40)
CREATE OR REPLACE FUNCTION mort_v ()
RETURNS TABLE (
zamount int,
ztype text,
zapp int,
zowe double precision
) AS $$
DECLARE
var_r record;
charlie double precision;
sam double precision;
BEGIN
charlie = 0;
FOR var_r IN(SELECT
amount,
"type",
app
FROM mort order by 1)
LOOP
zamount = var_r.amount;
ztype = var_r.type;
zapp = var_r.app;
sam = var_r.app - charlie;
if ztype = 'a' then
zowe = sam;
else
zowe = greatest(sam, 0);
end if;
charlie = charlie + zowe;
RETURN NEXT;
END LOOP;
END; $$
LANGUAGE 'plpgsql';
select * from mort_v()
So with my limited skills you'll notice I had to add a 'z' in front of the columns that are already in the table so I can spit it out again. If your table has 30 columns you'd normally have to do this 30 times. But, I asked a real engineer and he mentioned that if you just spit out the primary key with the calculated column, you can just join it back to the original table. That's smarter than what I have. If there's an even better solution, that would be great. This does serve as a nice reference to how to do something like a cursor in postgre and how to make variables without a '#' in front like in mssqlserver.
I was trying to make a function to work in db2:
CREATE FUNCTION TO_DATE8(DATE_STRING numeric(8,0))
RETURNS DATE
LANGUAGE SQL
IF DATE_STRING > 0 THEN
// ERROR ->
RETURN DATE ( TO_DATE ( SUBSTR ( DATE_STRING , 1 , 8 ) , 'YYYYMMDD' ) )
ELSE
RETURN DATE ( TO_DATE ( '00000000' , 'YYYYMMDD' ) )
END IF
END
ERROR: DATE IS NOT VALID
What to do?
The form of the procedure required seems to be like this (at least on the iSeries version):
CREATE FUNCTION TO_DATE8(DATE_STRING numeric(8,0))
RETURNS DATE
LANGUAGE SQL
BEGIN
RETURN(CASE WHEN DATE_STRING > 0 THEN DATE(SUBSTR(DATE_STRING, 1, 4) || '-' ||
SUBSTR(DATE_STRING, 5, 2) || '-' ||
SUBSTR(DATE_STRING, 7, 2))
ELSE DATE('0001-01-01')
END);
END
However:
Your procedure is misnamed (reading from a date-8, not to it).
Your DATE_STRING is not a string (or even a char), it's numeric. Please rename it to something that does not include the datatype (dateToConvert works)
You seem to want to return something that is not a valid date (all 0s). I'm returning *loval here, although it's possible it should actually be null.
I didn't put in enough checks for a valid date - this will blow up really easily.
If at all possible, the database should be changed to contain actual dates, not a numeric value. Disk is (relative to programmer/architect headaches) cheap.
You may also find a calendar file helpful, if the 8-digit numeric was one of the included columns.
For the benifit of others, this can be done in one line rather than a function:
CASE WHEN MYDATE = 0 THEN NULL ELSE DATE(INSERT(INSERT(LEFT(CHAR(MYDATE),8),5,0,'-'),8,0,'-')) END
MYDATE was 8 packed in my case.