What is the difference between TRANSLATE and REPLACE in sql? - database

select translate('flipflop','fl','h') from dual;
select replace('flipflop','fl','h') from dual;
These two queries give the same output,then why do we have different commands for carrying out the same operation?

Translate translate the string byte by byte
The a is replaced with an e, the h has no complement and is dropped.
SELECT TRANSLATE('So What', 'ah', 'e')
FROM dual;
Replace only occurance of word with specified word if match found like o with ay
SELECT REPLACE('So What', 'o', 'ay')
FROM dual;
UG
see https://community.oracle.com/thread/676170

REPLACE TRANSLATE
Replaces entire string at a time Replaces character one-to-one basis
Returns string if no match found Returns null if no match found

Related

Is there a way to find values that contain only 0's and a symbol of any length?

I want to find strings of any length that contain only 0's and a symbol such as a / a . or a -
Examples include 0__0 and 000/00/00000 and .00000
Considering this sample data:
CREATE TABLE dbo.things(thing varchar(255));
INSERT dbo.things(thing) VALUES
('0__0'),('000/00/00000'),('00000'),('0123456');
Try the following, which locates the first position of any character that is NOT a 0, a decimal, a forward slash, or an underscore. PATINDEX returns 0 if the pattern is not found.
SELECT thing FROM dbo.things
WHERE PATINDEX('%[^0^.^/^_]%', thing) = 0;
Results:
thing
0__0
000/00/00000
00000
The opposite:
SELECT thing FROM dbo.things
WHERE PATINDEX('%[^0^.^/^_]%', thing) > 0;
Results:
thing
0123food456
Example db<>fiddle
I can see a way of doing this... But it's something that wouldn't perform well, if you think about using it as a search criteria.
We are going to use a translate function on SQL Server, to replace the allowed characters, or symbols as you've said, with a zero. And then, eliminates the zeroes. If the result is an empty string, then there are two cases, or it only had zeroes and allowed characters, or it already was an empty string.
So, checking for this and for non-empty strings, we can define if it matches your criteria.
-- Test scenario
create table #example (something varchar(200) )
insert into #example(something) values
--Example cases from Stack Overflow
('0__0'),('000/00/00000'),('.00000'),
-- With something not allowed (don't know, just put a number)
('1230__0'),('000/04560/00000'),('.00000789'),
-- Just not allowed characters, zero, blank, and NULL
('1234567489'),('0'), (''),(null)
-- Shows the data, with a column to check if it matches your criteria
select *
from #example e
cross apply (
select case when
-- If it *must* have at least a zero
e.something like '%0%' and
-- Eliminates zeroes
replace(
-- Replaces the allowed characters with zero
translate(
e.something
,'_./'
,'000'
)
,'0'
,''
) = ''
then cast(1 as bit)
else cast(0 as bit)
end as doesItMatch
) as criteria(doesItMatch)
I really discourage you from using this as a search criteria.
-- Queries the table over this criteria.
-- This is going to compute over your entire table, so it can get very CPU intensive
select *
from #example e
where
-- If it *must* have at least a zero
e.something like '%0%' and
-- Eliminates zeroes
replace(
-- Replaces the allowed characters with zero
translate(
e.something
,'_./'
,'000'
)
,'0'
,''
) = ''
If you must use this as a search criteria, and this will be a common filter on your application, I suggest you create a new bit column, to flag if it matches this, and index it. Thus, the increase in computational effort would be spread on the inserts/updates/deletes, and the search queries won't overloading the database.
The code can be seen executing here, on DB Fiddle.
What I got from the question is that the strings must contain both 0 and any combination of the special characters in the string.
If you have SQL Server 2017 and above, you can use translate() to replace multiple characters with a space and compare this with the empty string. Also you can use LIKE to enforce that both a 0 and any combination of the special character(s) appear at least once:
DECLARE #temp TABLE (val varchar(100))
INSERT INTO #temp VALUES
('0__0'), ('000/00/00000'), ('.00000'), ('w0hee/'), ('./')
SELECT *
FROM #temp
WHERE val LIKE '%0%' --must have at least one zero somewhere
AND val LIKE '%[_/.]%' --must have at least one special character(s) somewhere
AND TRANSLATE(val, '0./_', ' ') = '' --translated zeros and sp characters to spaces equivalent to an empty string
Creates output:
val
0__0
000/00/00000
.00000

SQL Server - How to get last numeric value in the given string

I am trying to get last numeric part in the given string.
For Example, below are the given strings and the result should be last numeric part only
SB124197 --> 124197
287276ACBX92 --> 92
R009321743-16 --> 16
How to achieve this functionality. Please help.
Try this:
select right(#str, patindex('%[^0-9]%',reverse(#str)) - 1)
Explanation:
Using PATINDEX with '%[^0-9]%' as a search pattern you get the starting position of the first occurrence of a character that is not a number.
Using REVERSE you get the position of the first non numeric character starting from the back of the string.
Edit:
To handle the case of strings not containing non numeric characters you can use:
select case
when patindex(#str, '%[^0-9]%') = 0 then #str
else right(#str, patindex('%[^0-9]%',reverse(#str)) - 1)
end
If your data always contains at least one non-numeric character then you can use the first query, otherwise use the second one.
Actual query:
So, if your table is something like this:
mycol
--------------
SB124197
287276ACBX92
R009321743-16
123456
then you can use the following query (works in SQL Server 2012+):
select iif(x.i = 0, mycol, right(mycol, x.i - 1))
from mytable
cross apply (select patindex('%[^0-9]%', reverse(mycol) )) as x(i)
Output:
mynum
------
124197
92
16
123456
Demo here
Here is one way using Patindex
SELECT RIGHT(strg, COALESCE(NULLIF(Patindex('%[^0-9]%', Reverse(strg)), 0) - 1, Len(strg)))
FROM (VALUES ('SB124197'),
('287276ACBX92'),
('R009321743-16')) tc (strg)
After reversing the string, we are finding the position of first non numeric character and extracting the data from that position till the end..
Result :
-----
124197
92
16

Changing character in a string of characters

I was wondering regarding how to edit the following column that exists in oracle DB
PPPPFPPPPPPPPPPPPPPPPPPPPPPPPFPPPPPPPP
I want to only set the 5th F with P without affecting other structure.
I've around 700 records and I want to change that position (5th) on all users to P
I was thinking of PLSQL instead of a query, so could you please advice.
Thanks
Use REGEXP_REPLACE:
> SELECT REGEXP_REPLACE('PPPPFPPPPPPPPPPPPPPPPPPPPPPPPFPPPPPPPP', '^(\w{4}).(.*)', '\1P\2') AS COL_REGX FROM dual
COL_REGX
--------------------------------------
PPPPPPPPPPPPPPPPPPPPPPPPPPPPPFPPPPPPPP
Klashxx answer is a good one - REGEXP_REPLACE is the way to go. Old fashioned way built up bit by bit so you can see what's going on :
WITH
test_data (text)
AS (SELECT '1234F1234F1234F1234F1234F1234F1234' FROM DUAL
)
SELECT
text
,INSTR(text,'F',1,5) --fifth occurence
,SUBSTR(text,1,INSTR(text,'F',1,5)-1) --substr up to that point
,SUBSTR(text,1,INSTR(text,'F',1,5)-1)||'P' --add P
,SUBSTR(text,1,INSTR(text,'F',1,5)-1)||'P'||SUBSTR(text,INSTR(text,'F',1,5)+1) --add remainder of string
FROM
test_data
;
So what you're trying to do would be something like
UPDATE <your table>
SET <your column> = SUBSTR(<your column>,1,INSTR(<your column>,'F',1,5)-1)||'P'||SUBSTR(<your column>,INSTR(<your column>,'F',1,5)+1)
..assuming you want to update all rows
The solution below looks for the first five characters at the beginning of the input string. If found, it keeps the first four unchanged and it replaces the fifth with the letter P. Note that if the input string is four characters or less, it is left unchanged. (This includes NULL as the input string, shown in the WITH clause which creates sample strings and also in the output - note that the output has FIVE rows, even though there is nothing visible in the last one.)
with
test_data ( str ) as (
select 'ABCDEFGH' from dual union all
select 'PPPPF' from dual union all
select 'PPPPP' from dual union all
select '1234' from dual union all
select null from dual
)
select str, regexp_replace(str, '^(.{4}).', '\1P') as replaced
from test_data
;
STR REPLACED
-------- --------
ABCDEFGH ABCDPFGH
PPPPF PPPPP
PPPPP PPPPP
1234 1234
5 rows selected.
Flip the 5th 'bit' to a 'P' where it's currently an 'F'.
update table
set column = regexp_replace(column , '^(.{4}).', '\1P')
where regexp_like(column , '^.{4}F');

Make substring using a specific delimiter in SQL

I want to make a substring of a column value using a specific delimiter.I tried SUBSTRING_INDEX,but it doesn't work for SQL.Is there any way to achieve this??
Column values are:
ARTCSOFT-1111
ARTCSOFT-1112
ARTCSOFT-1113
and I want to achieve the same thing in SQL:
SUBSTRING_INDEX(Code,'SOFT-',1))
i.e I want the number after SOFT- in my substring.I can't use only - because before SOFT- there is chance that - may occur(rare case,but I don't want to take a chance)
Try using just SUBSTRING . For example
SELECT
SUBSTRING(code, CHARINDEX('SOFT-', code) + 5, LEN(code)) AS [name] from dbo.yourtable
hope this helps.
Tested Result:
SELECT RIGHT(Code , CHARINDEX ('-' ,REVERSE(Code))-1)
Read this as: Get the rightmost string after the first '-' in a reversed string - which is the same as the string after the last '-' character.
Try This Query:
select substring(col,charindex('-',col)+1,len(col)-charindex('-',col)) from #Your_table
Explanation of Query:
Here Charindex find the '-' delimeter [length] IN Given String and now that Result[length+1] is our starting point and ending length is [len(col)-starting length] gives ending point and then use substring Function to split a string according to our requirement.
Result of Query:
Required_col
1111
1112
1113

sql like statement picking up unexpected results

I have a simple table like the following
id, target
-----------
1, test_1
2, test_2
3, test_3
4, testable
I have a simple query like so:
select * from my_table where target like 'test_%'
What I'm expecting are the first 3 records but I'm getting all 4 records
See SQLFiddle example here
Underscore is a pattern matching character. Try this:
select * from my_table where target like 'test[_]%'
_ is also a wildcard. You can escape it like:
... like 'test\_%' escape '\'
The underscore character _ as you've used it is a wildcard for a single character, hence it returns 4 rows. Try using [_] instead of _.
To illustrate..
CREATE TABLE #tmp (val varchar(10))
INSERT INTO #tmp (val)
VALUES ('test_1'), ('test_2'), ('test_3'), ('testing')
-- This returns all four
SELECT * FROM #tmp WHERE val LIKE 'test_%'
-- This returns the three test_ rows
SELECT * FROM #tmp WHERE val LIKE 'test[_]%'
The underscore is a wildcard character that says "match any character single character", just like the % is a wildcard that says "match any 0 or more characters". If you're familiar with Regular Expressions, the underscore character is equivalent to the dot there. You'll need to properly escape the underscore to match that character literally.

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