How to extract letters from a string using Firebird SQL - firebird

I want to implement a stored procedure that extract letters from a varchar in firebird.
Example :
v_accountno' is of type varchar(50) and has the following values
accountno 1 - 000023208821
accountno 2 - 390026826850868140H
accountno 3 - 0700765001003267KAH
I want to extract the letters from v_accountno and output it in o_letter.
In my example: o_letter will store H for accountno 2 and KAH for accountno 3.
I tried the following stored procedure, which obviously won't work for accountno 3. (Please help).
CREATE OR ALTER PROCEDURE SP_EXTRACT_LETTER
returns (
o_letter varchar(50))
as
declare variable v_accountno varchar(50);
begin
v_accountno = '390026826850868140H';
if (not (:v_accountno similar to '[[:DIGIT:]]*')) then
begin
-- My SP won't work in for accountno 3 '0700765001003267KAH'
v_accountno = longsubstr(v_accountno, strlen(v_accountno), strlen(v_accountno));
o_letter = v_accountno;
end
suspend;
end


One solution would be to replace every digits with empty string like:
o_letter = REPLACE(v_accountno, '0', '')
o_letter = REPLACE(o_letter, '1', '')
o_letter = REPLACE(o_letter, '2', '')
...


Since Firebird 3, you can use substring for this, using its regex facility (using the similar clause):
substring(v_accountno similar '[[:digit:]]*#"[[:alpha:]]*#"' escape '#')
See also this dbfiddle.

Related

How can I return the first 3 characters after every comma in a string in TSQL

I have a string that I need to seperate into values seperated by commas. I have achieved this part with the below REPLACE statement:
declare #mc varchar(200)
declare #mc1 varchar(200)
select #mc = 'FRED&#g4;&#4g;MARY&#g4;&#4g;BILL&#g4;&#4g;TIMOTHY&#g4;&#4g;JOHNATHAN'
select #mc1 = REPLACE(#mc, '&#g4;&#4g;',', ')
The replace returns a string 'FRED, MARY, BILL, TIMOTHY, JOHNATHAN'
I then want to have another variable that will return the first 3 characters of each value before the commas, so the above string would be returned as:
'FRE, MAR, TIM, JOH'
Anyone know how I can achieve this?
Also happy for this to be done directly to the original #mc variable

ON SQL Server 2017+ you can make use of openJson to split the string into manageble segments and then string_agg to assemble the desired result:
declare #mc varchar(100)='FRED&#g4;&#4g;MARY&#g4;&#4g;BILL&#g4;&#4g;TIMOTHY&#g4;&#4g;JOHNATHAN'
select String_Agg(v, ', ')
from (select #mc)x(s)
cross apply (
select Left(j.[value],3) v, Convert(tinyint,j.[key]) Seq
from OpenJson(Concat('["',replace(s,';', '","'),'"]')) j
where Convert(tinyint,j.[key]) % 2 = 0
)j;
Demo Fiddle

What is PostgreSQL equivalent for MSSQL STR ( float_expression [ , length [ , decimal ] ] ) function?

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 $$
select case when length(val) > length_in
then rpad('*',length_in,'*') -- or just '**'
else lpad(val,length_in,'#') -- for demo using #, for real use ' '
end
from (select round(value_in, dec_len_in )::text) sq(val)
$$;

DB2: Converting varchar to money

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| |

How to use IIf function inside IN Clause?

I have a stored procedure as under
ALTER PROCEDURE [dbo].[usp_testProc]
(#Product NVARCHAR(200) = '',
#BOMBucket NVARCHAR(100) = '')
--exec usp_testProc '','1'
AS
BEGIN
SELECT *
FROM Mytbl x
WHERE 1 = 1
AND (#Product IS NULL OR #Product = '' OR x.PRODUCT = #Product)
AND (#BOMBucket IS NULL OR #BOMBucket = '' OR CAST(x.BOMBucket AS NVARCHAR(100)) IN (IIF(#BOMBucket != '12+', #BOMBucket, '13,14')))
END
Everything else if working fine except when I am passing the bucket value as 12+ . It should ideally show the result for bucket 13 and 14. But the result set is blank.
I know IN expects values as ('13','14'). But somehow not able to fit it in the program.

You can express that logic in a Boolean expression.
...
(#BOMBucket <> '12+'
AND cast(x.BOMBucket AS nvarchar(100)) = #BOMBucket
OR #BOMBucket = '12+'
AND cast(x.BOMBucket AS nvarchar(100)) IN ('13', '14'))
...
But casting the column prevents indexes from being used. You rather should cast the other operand. Like in:
x.BOMBucket = cast(#BOMBucket AS integer)
But then you had the problem, that the input must not be a string representing an inter but can be any string. this would cause an error when casting. In newer SQL Server versions you could circumvent that by using try_cast() but not in 2012 as far as I know. Maybe you should rethink your approach overall and pass a table variable with the wanted BOMBucket as integers instead.

How to find/replace weird whitespace in string

I find in my sql database string whit weird whitespace which cannot be replace like REPLACE(string, ' ', '') RTRIM and cant it even find with string = '% %'. This space is even transfered to new table when using SELECT string INTO
If i select this string in managment studio and copy that is seems is normal space and when everything is works but cant do nothing directly from database. What else can i do? Its some kind of error or can i try some special character for this?

First, you must identify the character.
You can do that by using a tally table (or a cte) and the Unicode function:
The following script will return a table with two columns: one contains a char and the other it's unicode value:
DECLARE #Str nvarchar(100) = N'This is a string containing 1 number and some words.';
with Tally(n) as
(
SELECT TOP(LEN(#str)) ROW_NUMBER() OVER(ORDER BY ##SPID)
FROM sys.objects a
--CROSS JOIN sys.objects b -- (unremark if there are not enough rows in the tally cte)
)
SELECT SUBSTRING(#str, n, 1) As TheChar,
UNICODE(SUBSTRING(#str, n, 1)) As TheCode
FROM Tally
WHERE n <= LEN(#str)
You can also add a condition to the where clause to only include "special" chars:
AND SUBSTRING(#str, n, 1) NOT LIKE '[a-zA-Z0-9]'
Then you can replace it using it's unicode value using nchar (I've used 32 in this example since it's unicode "regular" space:
SELECT REPLACE(#str, NCHAR(32), '|')
Result:
This|is|a|string|containing|1|number|and|some|words.