SubString function in sql server - sql-server

I am beginner in database PL/SQL . I am using the substring function for
#String = 'Y1223456883002'
in SQL Server like
SUBSTRING(#String,LEN(#String),2)
to get the last two numbers, but here output is only 2.
Can someone explain to me how to get the last two numbers with the zero?

To get the last 2 characters of a string in SQL Server you should use
DECLARE #string varchar(10) = 'Y1223456883002'
SELECT RIGHT(#string, 2)
If you want to use the substring function like you mentioned you should (as #Barry mentioned) use:
DECLARE #string varchar(10) = 'Y1223456883002'
SELECT SUBSTRING(#string, LEN(#string)-2, 2)
And another way to do it is by stuffing empty strings in place of the characters before the last 2:
DECLARE #string varchar(10) = 'Y1223456883002'
SELECT STUFF(#string, 1, LEN(#string)-2, '')
Performance wise they are all about the same (about 10 seconds for 10 million iterations on my laptop).

Related

"Create sql function , select english characters?"

I am looking for a function that selects English numbers and letters only:
Example:
TEKA תנור ביל דין in HLB-840 P-WH לבן
I want to run a function and get the following result:
TEKA HLB-840 P-WH
I'm using MS SQL Server 2012
What you really need here is regex replacement, which SQL Server does not support. Broadly speaking, you would want to find [^A-Za-z0-9 -]+\s* and then replace with empty string. Here is a demo showing that this works as expected:
Demo
This would output TEKA in HLB-840 P-WH for the input you provided. You might be able to do this in SQL Server using a regex package or UDF. Or, you could do this replacement outside of SQL using any number of tools which support regex (e.g. C#).
SQL-Server is not the right tool for this.
The following might work for you, but there is no guarantee:
declare #yourString NVARCHAR(MAX)=N'TEKA תנור ביל דין in HLB-840 P-WH לבן';
SELECT REPLACE(REPLACE(REPLACE(REPLACE(CAST(#yourString AS VARCHAR(MAX)),'?',''),' ','|~'),'~|',''),'|~',' ');
The idea in short:
A cast of NVARCHAR to VARCHAR will return all characters in your string, which are not known in the given collation, as question marks. The rest is replacements of question marks and multi-blanks.
If your string can include a questionmark, you can replace it first to a non-used character, which you re-replace at the end.
If you string might include either | or ~ you should use other characters for the replacements of multi-blanks.
You can influence this approach by specifying a specific collation, if some characters pass by...
there is no build in function for such purpose, but you can create your own function, should be something like this:
--create function (split string, and concatenate required)
CREATE FUNCTION dbo.CleanStringZZZ ( #string VARCHAR(100))
RETURNS VARCHAR(100)
BEGIN
DECLARE #B VARCHAR(100) = '';
WITH t --recursive part to create sequence 1,2,3... but will better to use existing table with index
AS
(
SELECT n = 1
UNION ALL
SELECT n = n+1 --
FROM t
WHERE n <= LEN(#string)
)
SELECT #B = #B+SUBSTRING(#string, t.n, 1)
FROM t
WHERE SUBSTRING(#string, t.n, 1) != '?' --this is just an example...
--WHERE ASCII(SUBSTRING(#string, t.n, 1)) BETWEEN 32 AND 127 --you can use something like this
ORDER BY t.n;
RETURN #B;
END;
and then you can use this function in your select statement:
SELECT dbo.CleanStringZZZ('TEKA תנור ביל דין in HLB-840 P-WH לבן');
create function dbo.AlphaNumericOnly(#string varchar(max))
returns varchar(max)
begin
While PatIndex('%[^a-z0-9]%', #string) > 0
Set #string = Stuff(#string, PatIndex('%[^a-z0-9]%', #string), 1, '')
return #string
end

What is the encode(<columnName>, 'escape') PostgreSQL equivalent in SQL Server?

In the same vein as this question, what is the equivalent in SQL Server to the following Postgres statement?
select encode(some_field, 'escape') from only some_table
As you were told already, SQL-Server is not the best with such issues.
The most important advise to avoid such issues is: Use the appropriate data type to store your values. Storing binary data as a HEX-string is running against this best practice. But there are some workarounds:
I use the HEX-string taken from the linked question:
DECLARE #str VARCHAR(100)='0x61736461640061736461736400';
--here I use dynamically created SQL to get the HEX-string as a real binary:
DECLARE #convBin VARBINARY(MAX);
DECLARE #cmd NVARCHAR(MAX)=N'SELECT #bin=' + #str;
EXEC sp_executeSql #cmd
,N'#bin VARBINARY(MAX) OUTPUT'
,#bin=#convBin OUTPUT;
--This real binary can be converted to a VARCHAR(MAX).
--Be aware, that in this case the input contains 00 as this is an array.
--It is possible to split the input at the 00s, but this is going to far...
SELECT #convBin AS HexStringAsRealBinary
,CAST(#convBin AS VARCHAR(MAX)) AS CastedToString; --You will see the first "asda" only
--If your HEX-string is not longer than 10 bytes there is an undocumented function:
--You'll see, that the final AA is cut away, while a shorter string would be filled with zeros.
SELECT sys.fn_cdc_hexstrtobin('0x00112233445566778899AA')
SELECT CAST(sys.fn_cdc_hexstrtobin(#str) AS VARCHAR(100));
UPDATE: An inlinable approach
The following recursive CTE will read the HEX-string character by character.
Furthermore it will group the result and return two rows in this case.
This solution is very specific to the given input.
DECLARE #str VARCHAR(100)='0x61736461640061736461736400';
WITH recCTE AS
(
SELECT 1 AS position
,1 AS GroupingKey
,SUBSTRING(#str,3,2) AS HEXCode
,CHAR(SUBSTRING(sys.fn_cdc_hexstrtobin('0x' + SUBSTRING(#str,3,2)),1,1)) AS TheLetter
UNION ALL
SELECT r.position+1
,r.GroupingKey + CASE WHEN SUBSTRING(#str,2+(r.position)*2+1,2)='00' THEN 1 ELSE 0 END
,SUBSTRING(#str,2+(r.position)*2+1,2)
,CHAR(SUBSTRING(sys.fn_cdc_hexstrtobin('0x' + SUBSTRING(#str,2+(r.position)*2+1,2)),1,1)) AS TheLetter
FROM recCTE r
WHERE position<LEN(#str)/2
)
SELECT r.GroupingKey
,(
SELECT x.TheLetter AS [*]
FROM recCTE x
WHERE x.GroupingKey=r.GroupingKey
AND x.HEXCode<>'00'
AND LEN(x.HEXCode)>0
ORDER BY x.position
FOR XML PATH(''),TYPE
).value('.','varchar(max)')
FROM recCTE r
GROUP BY r.GroupingKey;
The result
1 asdad
2 asdasd
Hint: Starting with SQL Server 2017 there is STRING_AGG(), which would reduce the final SELECT...
If you need this functionality, it's going to be up to you to implement it. Assuming you just need the escape variant, you can try to implement it as a T-SQL UDF. But pulling strings apart, working character by character and building up a new string just isn't a T-SQL strength. You'd be looking at a WHILE loop to count over the length of the input byte length, SUBSTRING to extract the individual bytes, and CHAR to directly convert the bytes that don't need to be octal encoded.1
If you're going to start down this route (and especially if you want to support the other formats), I'd be looking at using the CLR support in SQL Server, to create the function in a .NET language (C# usually preferred) and use the richer string manipulation functionality there.
Both of the above assume that what you're really wanting is to replicate the escape format of encode. If you just want "take this binary data and give me a safe string to represent it", just use CONVERT to get the binary hex encoded.
1Here's my attempt at it. I'd suggest a lot of testing and tweaking before you use it in anger:
create function Postgresql_encode_escape (#input varbinary(max))
returns varchar(max)
as
begin
declare #i int
declare #len int
declare #out varchar(max)
declare #chr int
select #i = 1, #out = '',#len = DATALENGTH(#input)
while #i <= #len
begin
set #chr = SUBSTRING(#input,#i,1)
if #chr > 31 and #chr < 128
begin
set #out = #out + CHAR(#chr)
end
else
begin
set #out = #out + '\' +
RIGHT('000' + CONVERT(varchar(3),
(#chr / 64)*100 +
((#chr / 8)%8)*10 +
(#chr % 8))
,3)
end
set #i = #i + 1
end
return #out
end

Format a numeric field as text with fixed pattern sql server 2008

I have a numeric field (field1) that has numeric values 1.2, 23.72, 14.02 etc.
I need to present this as a fixed text field format 13 characters as 000000000.000 e.g. 23.72 must display 000000023.720 (9 digits with 3 decimals)Server 2008
What is the best way to do this ?
You can use the following query:
SELECT FORMAT(ColumnName, '000000000.000') FROM TableName
I'm not saying this is the best way, as the final presentation layer (your webpage) might still render it as a numeric value that will follow the format defined on that layer.
You can use FORMAT(#input, '000000000.000') but that won't give you intended output for longer numbers.
You can make your own function which pads zeros ahead and otherwise stops your execution in case of longer numbers.
DECLARE #input NUMERIC(20,7);
DECLARE #number NUMERIC(12,3);
DECLARE #output VARCHAR(13)
SET #input = 123620;
SET #number = CONVERT(NUMERIC(12,3), #input)
SET #output = CONVERT(CHAR(13), #number)
SET #output = REPLICATE('0', 10 - CHARINDEX('.',#output)) + #output
try this,
Declare #i float=23.72
declare #j decimal(18,3)=#i
select #j
select replicate('0',13-len(#j))+cast(#j as varchar)
and tell that for which data it do not work.
Or try this one
SELECT LEFT(RIGHT(REPLICATE('0',12) + CAST('23.72' AS VARCHAR(10)),12) + REPLICATE('0',3),13)
output
000000023.720

Split comma delimited parameter being passed to stored procedure in SQL Server 2008 R2

I am being passed the following parameter to my stored procedure -
#AddOns = 23:2,33:1,13:5
I need to split the string by the commas using this -
SET #Addons = #Addons + ','
set #pos = 0
set #len - 0
While CHARINDEX(',', #Addons, #pos+1)>0
Begin
SET #len = CHARINDEX(','), #Addons, #pos+1) - #pos
SET #value = SUBSTRING(#Addons, #pos, #len)
So now #value = 23:2 and I need to get 23 which is my ID and 2 which is my quantity. Here is the rest of my code -
INSERT INTO TABLE(ID, Qty)
VALUES(#ID, #QTY)
set #pos = CHARINDEX(',', #Addons, #pos+#len) + 1
END
So what is the best way to get the values of 23 and 2 in separate fields to us in the INSERT statement?
First you would split the sets of key-value pairs into rows (and it looks like you already got that far), and then you get the position of the colon and use that to do two SUBSTRING operations to split the key and value apart.
Also, this can be done much more efficiently than storing each row's key and value into separate variables just to get inserted into a table. If you INSERT from the SELECT that breaks this data apart, it will be a set-based operation instead of row-by-row.
For example:
DECLARE #AddOns VARCHAR(1000) = N'23:2,33:1,13:5,999:45';
;WITH pairs AS
(
SELECT [SplitVal] AS [Value], CHARINDEX(N':', [SplitVal]) AS [ColonIndex]
FROM SQL#.String_Split(#AddOns, N',', 1) -- https://SQLsharp.com/
)
SELECT *,
SUBSTRING(pairs.[Value], 1, pairs.[ColonIndex] - 1) AS [ID],
SUBSTRING(pairs.[Value], pairs.[ColonIndex] + 1, 1000) AS [QTY]
FROM pairs;
/*
Value ColonIndex ID QTY
23:2 3 23 2
33:1 3 33 1
13:5 3 13 5
999:45 4 999 45
*/
GO
For that example I am using a SQLCLR string splitter found in the SQL# library (that I am the author of), which is available in the Free version. You can use whatever splitter you like, including the built-in STRING_SPLIT that was introduced in SQL Server 2016.
It would be used as follows:
DECLARE #AddOns VARCHAR(1000) = N'23:2,33:1,13:5,999:45';
;WITH pairs AS
(
SELECT [value] AS [Value], CHARINDEX(N':', [value]) AS [ColonIndex]
FROM STRING_SPLIT(#AddOns, N',') -- built-in function starting in SQL Server 2016
)
INSERT INTO dbo.TableName (ID, QTY)
SELECT SUBSTRING(pairs.[Value], 1, pairs.[ColonIndex] - 1) AS [ID],
SUBSTRING(pairs.[Value], pairs.[ColonIndex] + 1, 1000) AS [QTY]
FROM pairs;
Of course, the Full (i.e. paid) version of SQL# includes an additional splitter designed to handle key-value pairs. It's called String_SplitKeyValuePairs and works as follows:
DECLARE #AddOns VARCHAR(1000) = N'23:2,33:1,13:5,999:45';
SELECT *
FROM SQL#.String_SplitKeyValuePairs(#AddOns, N',', N':', 1, NULL, NULL, NULL);
/*
KeyID Key Value
1 23 2
2 33 1
3 13 5
4 999 45
*/
GO
So, it would be used as follows:
DECLARE #AddOns VARCHAR(1000) = N'23:2,33:1,13:5,999:45';
INSERT INTO dbo.[TableName] ([Key], [Value])
SELECT kvp.[Key], kvp.[Value]
FROM SQL#.String_SplitKeyValuePairs(#AddOns, N',', N':', 1, NULL, NULL, NULL) kvp;
Check out this blog post...
http://www.sqlservercentral.com/blogs/querying-microsoft-sql-server/2013/09/19/how-to-split-a-string-by-delimited-char-in-sql-server/
Noel
I am going to make another attempt at this inspired by the answer given by #gofr1 on this question...
How to insert bulk of column data to temp table?
That answer showed how to use an XML variable and the nodes method to split comma separated data and insert it into individual columns in a table. It seemed to me to be very similar to what you were trying to do here.
Check out this SQL. It certainly isn't has concise as just having "split" function, but it seems better than chopping up the string based on position of the colon.
Noel

Remove the 7th digit of a bigint for every row in a Sql Server table

I am maintaining SQL Server database and some c# code which uploads data to it from a third party. The database has a table 'LessonRoom' which contains a row for each lesson which occurs in a particluar room, it has a field 'SourceKey' which is a bigint and is formed by concatenating a room id and a lesson id, the c# which returns this key is as follows:
SourceKey = long.Parse(RoomId.ToString().PadRight(7, '0') + LessonId.ToString());
This code started falling over because the lessonId's grew too large and the resulting int is too large to fit in a bigint (c# long). The RoomIds are only ever 5 digits long so an easy fix is to PadRight(6, '0').
Now I have a solution but I need to update the existing data. I don't know how to remove a zero from the 7th digit of a SQL Server bigint in every row of 500,000 rows. Do I have to write a query to convert the value to a string, remove the zero, parse and put it back or can anyone think of a more succinct way to do it?
Essentially I need to turn this number:
6,159,800,830,114,069,893
Into this one:
615,980,830,114,069,893
Sine you know it is always the 7th character you want to remove you can do this quite easily.
declare #SourceKey bigint = 6159800830114069893
select cast(stuff(cast(#SourceKey as varchar(25)), 7, 1, '') as bigint)
you could resolve them with the modulo-Operator :)
here a simple T SQL example
DECLARE #input AS BIGINT
DECLARE #expect AS BIGINT
DECLARE #rest AS BIGINT
DECLARE #result AS BIGINT
DECLARE #resultShort AS BIGINT
SET #input = 6159800830114069893
SET #expect= 615980830114069893
SET #rest = #input % 1000000000000
SET #result = ( ( #input - #rest ) / 10 ) + #rest
SET #resultShort = ( ( #input - #input % 1000000000000 ) / 10 ) + #input %
1000000000000
SELECT #rest, #result,
CASE
WHEN #result = #expect THEN 'true'
ELSE 'false'
END AS test,
#resultShort,
CASE
WHEN #resultShort = #expect THEN 'true'
ELSE 'false'
END AS test2

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