I have 2 tables:-
Table_1
GetID UnitID
1 1,2,3
2 4,5
3 5,6
4 6
Table_2
ID UnitID UserID
1 1 1
1 2 1
1 3 1
1 4 1
1 5 2
1 6 3
I want the 'GetID' based on 'UserID'.
Let me explain you with an example.
For e.g.
I want all the GetID where UserID is 1.
The result set should be 1 and 2. 2 is included because one of the Units of 2 has UserID 1.
I want all the GetID where UserID is 2
The result set should be 2 and 3. 2 is included because one of Units of 2 has UserID 2.
I want to achieve this.
Thank you in Advance.
You can try a query like this:
See live demo
select
distinct userid,getid
from Table_1 t1
join Table_2 t2
on t1.unitId+',' like '%' +cast(t2.unitid as varchar(max))+',%'
and t2.userid=1
The query for this will be relatively ugly, because you made the mistake of storing CSV data in the UnitID column (or maybe someone else did and you are stuck with it).
SELECT DISTINCT
t1.GetID
FROM Table_1 t1
INNER JOIN Table_2 t2
ON ',' + t1.UnitID + ',' LIKE '%,' + CONVERT(varchar(10), t2.UnitID) + ',%'
WHERE
t2.UserID = 1;
Demo
To understand the join trick being used here, for the first row of Table_1 we are comparing ,1,2,3, against other single UnitID values from Table_2, e.g. %,1,%. Hopefully it is clear that my logic would match a single UnitID value in the CSV string in any position, including the first and last.
But a much better long term approach would be to separate those CSV values across separate records. Then, in addition to requiring a much simpler query, you could take advantage of things like indices.
try this:
declare #Table_1 table(GetID INT, UnitId VARCHAR(10))
declare #Table_2 table(ID INT, UnitId INT,UserId INT)
INSERT INTO #Table_1
SELECT 1,'1,2,3'
union
SELECT 2,'4,5'
union
SELECT 3,'5,6'
union
SELECT 4,'6'
INSERT INTO #Table_2
SELECT 1,1,1
union
SELECT 1,2,1
union
SELECT 1,3,1
union
SELECT 1,4,1
union
SELECT 1,5,2
union
SELECT 1,6,3
declare #UserId INT = 2
DECLARE #UnitId VARCHAR(10)
SELECT #UnitId=COALESCE(#UnitId + ',', '') + CAST(UnitId AS VARCHAR(5)) from #Table_2 WHERE UserId=#UserId
select distinct t.GetId
from #Table_1 t
CROSS APPLY [dbo].[Split](UnitId,',') AS AA
CROSS APPLY [dbo].[Split](#UnitId,',') AS BB
WHERE AA.Value=BB.Value
Split Function:
CREATE FUNCTION [dbo].Split(#input AS Varchar(4000) )
RETURNS
#Result TABLE(Value BIGINT)
AS
BEGIN
DECLARE #str VARCHAR(20)
DECLARE #ind Int
IF(#input is not null)
BEGIN
SET #ind = CharIndex(',',#input)
WHILE #ind > 0
BEGIN
SET #str = SUBSTRING(#input,1,#ind-1)
SET #input = SUBSTRING(#input,#ind+1,LEN(#input)-#ind)
INSERT INTO #Result values (#str)
SET #ind = CharIndex(',',#input)
END
SET #str = #input
INSERT INTO #Result values (#str)
END
RETURN
END
I've got dirty data in a column with variable alpha length. I just want to strip out anything that is not 0-9.
I do not want to run a function or proc. I have a script that is similar that just grabs the numeric value after text, it looks like this:
Update TableName
set ColumntoUpdate=cast(replace(Columnofdirtydata,'Alpha #','') as int)
where Columnofdirtydata like 'Alpha #%'
And ColumntoUpdate is Null
I thought it would work pretty good until I found that some of the data fields I thought would just be in the format Alpha # 12345789 are not.
Examples of data that needs to be stripped
AB ABCDE # 123
ABCDE# 123
AB: ABC# 123
I just want the 123. It is true that all data fields do have the # prior to the number.
I tried substring and PatIndex, but I'm not quite getting the syntax correct or something. Anyone have any advice on the best way to address this?
See this blog post on extracting numbers from strings in SQL Server. Below is a sample using a string in your example:
DECLARE #textval NVARCHAR(30)
SET #textval = 'AB ABCDE # 123'
SELECT LEFT(SUBSTRING(#textval, PATINDEX('%[0-9.-]%', #textval), 8000),
PATINDEX('%[^0-9.-]%', SUBSTRING(#textval, PATINDEX('%[0-9.-]%', #textval), 8000) + 'X') -1)
Here is an elegant solution if your server supports the TRANSLATE function (on sql server it's available on sql server 2017+ and also sql azure).
First, it replaces any non numeric characters with a # character.
Then, it removes all # characters.
You may need to add additional characters that you know may be present in the second parameter of the TRANSLATE call.
select REPLACE(TRANSLATE([Col], 'abcdefghijklmnopqrstuvwxyz+()- ,#+', '##################################'), '#', '')
You can use stuff and patindex.
stuff(Col, 1, patindex('%[0-9]%', Col)-1, '')
SQL Fiddle
This works well for me:
CREATE FUNCTION [dbo].[StripNonNumerics]
(
#Temp varchar(255)
)
RETURNS varchar(255)
AS
Begin
Declare #KeepValues as varchar(50)
Set #KeepValues = '%[^0-9]%'
While PatIndex(#KeepValues, #Temp) > 0
Set #Temp = Stuff(#Temp, PatIndex(#KeepValues, #Temp), 1, '')
Return #Temp
End
Then call the function like so to see the original something next to the sanitized something:
SELECT Something, dbo.StripNonNumerics(Something) FROM TableA
In case if there are some characters possible between digits (e.g. thousands separators), you may try following:
declare #table table (DirtyCol varchar(100))
insert into #table values
('AB ABCDE # 123')
,('ABCDE# 123')
,('AB: ABC# 123')
,('AB#')
,('AB # 1 000 000')
,('AB # 1`234`567')
,('AB # (9)(876)(543)')
;with tally as (select top (100) N=row_number() over (order by ##spid) from sys.all_columns),
data as (
select DirtyCol, Col
from #table
cross apply (
select (select C + ''
from (select N, substring(DirtyCol, N, 1) C from tally where N<=datalength(DirtyCol)) [1]
where C between '0' and '9'
order by N
for xml path(''))
) p (Col)
where p.Col is not NULL
)
select DirtyCol, cast(Col as int) IntCol
from data
Output is:
DirtyCol IntCol
--------------------- -------
AB ABCDE # 123 123
ABCDE# 123 123
AB: ABC# 123 123
AB # 1 000 000 1000000
AB # 1`234`567 1234567
AB # (9)(876)(543) 9876543
For update, add ColToUpdate to select list of the data cte:
;with num as (...),
data as (
select ColToUpdate, /*DirtyCol, */Col
from ...
)
update data
set ColToUpdate = cast(Col as int)
CREATE FUNCTION FN_RemoveNonNumeric (#Input NVARCHAR(512))
RETURNS NVARCHAR(512)
AS
BEGIN
DECLARE #Trimmed NVARCHAR(512)
SELECT #Trimmed = #Input
WHILE PATINDEX('%[^0-9]%', #Trimmed) > 0
SELECT #Trimmed = REPLACE(#Trimmed, SUBSTRING(#Trimmed, PATINDEX('%[^0-9]%', #Trimmed), 1), '')
RETURN #Trimmed
END
GO
SELECT dbo.FN_RemoveNonNumeric('ABCDE# 123')
Pretty late to the party, I found the following which I though worked brilliantialy.. if anyone is still looking
SELECT
(SELECT CAST(CAST((
SELECT SUBSTRING(FieldToStrip, Number, 1)
FROM master..spt_values
WHERE Type='p' AND Number <= LEN(FieldToStrip) AND
SUBSTRING(FieldToStrip, Number, 1) LIKE '[0-9]' FOR XML Path(''))
AS xml) AS varchar(MAX)))
FROM
SourceTable
Here's a version which pulls all digits from a string; i.e. given I'm 35 years old; I was born in 1982. The average family has 2.4 children. this would return 35198224. i.e. it's good where you've got numeric data which may have been formatted as a code (e.g. #123,456,789 / 123-00005), but isn't appropriate if you're looking to pull out specific numbers (i.e. as opposed to digits / just the numeric characters) from the text. Also it only handles digits; so won't return negative signs (-) or periods .).
declare #table table (id bigint not null identity (1,1), data nvarchar(max))
insert #table (data)
values ('hello 123 its 45613 then') --outputs: 12345613
,('1 some other string 98 example 4') --outputs: 1984
,('AB ABCDE # 123') --outputs: 123
,('ABCDE# 123') --outputs: 123
,('AB: ABC# 123') --outputs: 123
; with NonNumerics as (
select id
, data original
--the below line replaces all digits with blanks
, replace(replace(replace(replace(replace(replace(replace(replace(replace(replace(data,'0',''),'1',''),'2',''),'3',''),'4',''),'5',''),'6',''),'7',''),'8',''),'9','') nonNumeric
from #table
)
--each iteration of the below CTE removes another non-numeric character from the original string, putting the result into the numerics column
, Numerics as (
select id
, replace(original, substring(nonNumeric,1,1), '') numerics
, replace(nonNumeric, substring(nonNumeric,1,1), '') charsToreplace
, len(replace(nonNumeric, substring(nonNumeric,1,1), '')) charsRemaining
from NonNumerics
union all
select id
, replace(numerics, substring(charsToreplace,1,1), '') numerics
, replace(charsToreplace, substring(charsToreplace,1,1), '') charsToreplace
, len(replace(charsToreplace, substring(charsToreplace,1,1), '')) charsRemaining
from Numerics
where charsRemaining > 0
)
--we select only those strings with `charsRemaining=0`; i.e. the rows for which all non-numeric characters have been removed; there should be 1 row returned for every 1 row in the original data set.
select * from Numerics where charsRemaining = 0
This code works by removing all the digits (i.e. the characters we want) from a the given strings by replacing them with blanks. Then it goes through the original string (which includes the digits) removing all of the characters that were left (i.e. the non-numeric characters), thus leaving only the digits.
The reason we do this in 2 steps, rather than just removing all non-numeric characters in the first place is there are only 10 digits, whilst there are a huge number of possible characters; so replacing that small list is relatively fast; then gives us a list of those non-numeric characters which actually exist in the string, so we can then replace that small set.
The method makes use of recursive SQL, using common table expressions (CTEs).
To add on to Ken's answer, this handles commas and spaces and parentheses
--Handles parentheses, commas, spaces, hyphens..
declare #table table (c varchar(256))
insert into #table
values
('This is a test 111-222-3344'),
('Some Sample Text (111)-222-3344'),
('Hello there 111222 3344 / How are you?'),
('Hello there 111 222 3344 ? How are you?'),
('Hello there 111 222 3344. How are you?')
select
replace(LEFT(SUBSTRING(replace(replace(replace(replace(replace(c,'(',''),')',''),'-',''),' ',''),',',''), PATINDEX('%[0-9.-]%', replace(replace(replace(replace(replace(c,'(',''),')',''),'-',''),' ',''),',','')), 8000),
PATINDEX('%[^0-9.-]%', SUBSTRING(replace(replace(replace(replace(replace(c,'(',''),')',''),'-',''),' ',''),',',''), PATINDEX('%[0-9.-]%', replace(replace(replace(replace(replace(c,'(',''),')',''),'-',''),' ',''),',','')), 8000) + 'X') -1),'.','')
from #table
Create function fn_GetNumbersOnly(#pn varchar(100))
Returns varchar(max)
AS
BEGIN
Declare #r varchar(max) ='', #len int ,#c char(1), #x int = 0
Select #len = len(#pn)
while #x <= #len
begin
Select #c = SUBSTRING(#pn,#x,1)
if ISNUMERIC(#c) = 1 and #c <> '-'
Select #r = #r + #c
Select #x = #x +1
end
return #r
End
In your case It seems like the # will always be after teh # symbol so using CHARINDEX() with LTRIM() and RTRIM() would probably perform the best. But here is an interesting method of getting rid of ANY non digit. It utilizes a tally table and table of digits to limit which characters are accepted then XML technique to concatenate back to a single string without the non-numeric characters. The neat thing about this technique is it could be expanded to included ANY Allowed characters and strip out anything that is not allowed.
DECLARE #ExampleData AS TABLE (Col VARCHAR(100))
INSERT INTO #ExampleData (Col) VALUES ('AB ABCDE # 123'),('ABCDE# 123'),('AB: ABC# 123')
DECLARE #Digits AS TABLE (D CHAR(1))
INSERT INTO #Digits (D) VALUES ('0'),('1'),('2'),('3'),('4'),('5'),('6'),('7'),('8'),('9')
;WITH cteTally AS (
SELECT
I = ROW_NUMBER() OVER (ORDER BY (SELECT NULL))
FROM
#Digits d10
CROSS APPLY #Digits d100
--add more cross applies to cover longer fields this handles 100
)
SELECT *
FROM
#ExampleData e
OUTER APPLY (
SELECT CleansedPhone = CAST((
SELECT TOP 100
SUBSTRING(e.Col,t.I,1)
FROM
cteTally t
INNER JOIN #Digits d
ON SUBSTRING(e.Col,t.I,1) = d.D
WHERE
I <= LEN(e.Col)
ORDER BY
t.I
FOR XML PATH('')) AS VARCHAR(100))) o
Declare #MainTable table(id int identity(1,1),TextField varchar(100))
INSERT INTO #MainTable (TextField)
VALUES
('6B32E')
declare #i int=1
Declare #originalWord varchar(100)=''
WHile #i<=(Select count(*) from #MainTable)
BEGIN
Select #originalWord=TextField from #MainTable where id=#i
Declare #r varchar(max) ='', #len int ,#c char(1), #x int = 0
Select #len = len(#originalWord)
declare #pn varchar(100)=#originalWord
while #x <= #len
begin
Select #c = SUBSTRING(#pn,#x,1)
if(#c!='')
BEGIN
if ISNUMERIC(#c) = 0 and #c <> '-'
BEGIN
Select #r = cast(#r as varchar) + cast(replace((SELECT ASCII(#c)-64),'-','') as varchar)
end
ELSE
BEGIN
Select #r = #r + #c
END
END
Select #x = #x +1
END
Select #r
Set #i=#i+1
END
I have created a function for this
Create FUNCTION RemoveCharacters (#text varchar(30))
RETURNS VARCHAR(30)
AS
BEGIN
declare #index as int
declare #newtexval as varchar(30)
set #index = (select PATINDEX('%[A-Z.-/?]%', #text))
if (#index =0)
begin
return #text
end
else
begin
set #newtexval = (select STUFF ( #text , #index , 1 , '' ))
return dbo.RemoveCharacters(#newtexval)
end
return 0
END
GO
Here is the answer:
DECLARE #t TABLE (tVal VARCHAR(100))
INSERT INTO #t VALUES('123')
INSERT INTO #t VALUES('123S')
INSERT INTO #t VALUES('A123,123')
INSERT INTO #t VALUES('a123..A123')
;WITH cte (original, tVal, n)
AS
(
SELECT t.tVal AS original,
LOWER(t.tVal) AS tVal,
65 AS n
FROM #t AS t
UNION ALL
SELECT tVal AS original,
CAST(REPLACE(LOWER(tVal), LOWER(CHAR(n)), '') AS VARCHAR(100)),
n + 1
FROM cte
WHERE n <= 90
)
SELECT t1.tVal AS OldVal,
t.tval AS NewVal
FROM (
SELECT original,
tVal,
ROW_NUMBER() OVER(PARTITION BY tVal + original ORDER BY original) AS Sl
FROM cte
WHERE PATINDEX('%[a-z]%', tVal) = 0
) t
INNER JOIN #t t1
ON t.original = t1.tVal
WHERE t.sl = 1
You can create SQL CLR scalar function in order to be able to use regular expressions like replace patterns.
Here you can find example of how to create such function.
Having such function will solve the issue with just the following lines:
SELECT [dbo].[fn_Utils_RegexReplace] ('AB ABCDE # 123', '[^0-9]', '');
SELECT [dbo].[fn_Utils_RegexReplace] ('ABCDE# 123', '[^0-9]', '');
SELECT [dbo].[fn_Utils_RegexReplace] ('AB: ABC# 123', '[^0-9]', '');
More important, you will be able to solve more complex issues as the regular expressions will bring a whole new world of options directly in your T-SQL statements.
Use this:
REPLACE(TRANSLATE(SomeString, REPLACE(TRANSLATE(SomeString, '0123456789', '##########'), '#', ''), REPLICATE('#', LEN(REPLACE(TRANSLATE(SomeString, '0123456789', '##########'), '#', '') + 'x') - 1)), '#', '')
Demo:
DROP TABLE IF EXISTS #MyTempTable;
CREATE TABLE #MyTempTable (SomeString VARCHAR(255));
INSERT INTO #MyTempTable
VALUES ('ssss123ssg99d362sdg')
, ('hey 62q&*^(n43')
, (NULL)
, ('')
, ('hi')
, ('123');
SELECT SomeString
, REPLACE(TRANSLATE(SomeString, REPLACE(TRANSLATE(SomeString, '0123456789', '##########'), '#', ''), REPLICATE('#', LEN(REPLACE(TRANSLATE(SomeString, '0123456789', '##########'), '#', '') + 'x') - 1)), '#', '')
FROM #MyTempTable;
DROP TABLE IF EXISTS #MyTempTable;
Results:
SomeString
(No column name)
ssss123ssg99d362sdg
12399362
hey62q&*^(n43
6243
NULL
NULL
hi
123
123
While the OP wanted to "strip out anything that is not 0-9", the post is also tagged with "substring" and "patindex", and the OP mentioned the concern "not quite getting the syntax correct or something". To address that the requirements note that "all data fields do have the # prior to the number" and to provide an answer that addresses the challenges with substring/patindex, consider the following:
/* A sample select */
;WITH SampleValues AS
( SELECT 'AB ABCDE # 123' [Columnofdirtydata]
UNION ALL SELECT 'AB2: ABC# 123')
SELECT
s.Columnofdirtydata,
f1.pos1,
'['+ f2.substr +']' [InspectOutput]
FROM
SampleValues s
CROSS APPLY (SELECT PATINDEX('%# %',s.Columnofdirtydata) [pos1]) f1
CROSS APPLY (SELECT SUBSTRING(s.Columnofdirtydata, f1.pos1 + LEN('#-'),LEN(s.Columnofdirtydata)) [substr]) f2
/* Using update scenario from OP */
UPDATE t1
SET t1.Columntoupdate = CAST(f2.substr AS INT)
FROM
TableName t1
CROSS APPLY (SELECT PATINDEX('%# %',t1.Columnofdirtydata) [pos1]) f1
CROSS APPLY (SELECT SUBSTRING(t1.Columnofdirtydata, f1.pos1 + LEN('#-'),LEN(t1.Columnofdirtydata)) [substr]) f2
Note that my syntax advice for patindex/substring, is to:
consider using APPLY as a way to temporarily alias results from one function for use as parameters in the next. It's not uncommon to (in ETL, for example) need to parse out parameter/position-based substrings in an updatable column of a staging table. If you need to "debug" and potentially fix some parsing logic, this style will help.
consider using LEN('PatternSample') in your substring logic, to account for reusing this pattern or adjusting it when your source data changes (instead of "+ 1"
SUBSTRING() requires a length parameter, but it can be greater than the length of the string. Therefore, if you are getting "the rest of the string" after the pattern, you can just use "The source length"
DECLARE #STR VARCHAR(400)
DECLARE #specialchars VARCHAR(50) = '%[~,#,#,$,%,&,*,(,),!^?:]%'
SET #STR = '1, 45 4,3 68.00-'
WHILE PATINDEX( #specialchars, #STR ) > 0
---Remove special characters using Replace function
SET #STR = Replace(Replace(REPLACE( #STR, SUBSTRING( #STR, PATINDEX( #specialchars, #STR ), 1 ),''),'-',''), ' ','')
SELECT #STR
SELECT REGEXP_REPLACE( col, '[^[:digit:]]', '' ) AS new_col FROM my_table
I have a table (no.1) which has 10 columns. One of them clm01 is integer and not allowed with null values.
There is a second table (no.2) which has many columns. One of them is string type clm02. An example of this column data is 1,2,3.
I'd like to make a query like:
select *
from table1 t1, table2 t2
where t1.clm01 not in (t2.clm2)
For example in table1 I have 5 records with values in clm01 1,2,3,4,5 and in table2 I've got 1 record with value in clm02 = 1,2,3
So I would like with the query to return only the record with the value 4 and 5 in the clm01.
Instead I get:
Conversion failed when converting the varchar value '1,2,3' to data type int
Any ideas?
Use STRING_SPLIT() function to split the comma separated values, if you are using SQL Server 2016.
SELECT *
FROM table1 t1
WHERE t1.clm1 NOT IN (SELECT Value FROM table2 t2
CROSS APPLY STRING_SPLIT(t2.clm2,','))
If you are using any lower versions of SQL server write a UDF to split string and use the function in CROSS APPLY clause.
CREATE FUNCTION [dbo].[SplitString]
(
#string NVARCHAR(MAX),
#delimiter CHAR(1)
)
RETURNS #output TABLE(Value NVARCHAR(MAX)
)
BEGIN
DECLARE #start INT, #end INT
SELECT #start = 1, #end = CHARINDEX(#delimiter, #string)
WHILE #start < LEN(#string) + 1 BEGIN
IF #end = 0
SET #end = LEN(#string) + 1
INSERT INTO #output (Value)
VALUES(SUBSTRING(#string, #start, #end - #start))
SET #start = #end + 1
SET #end = CHARINDEX(#delimiter, #string, #start)
END
RETURN
END
I decided to give you a couple of options but this really is a duplicate question I see pretty often.
There are two main ways of going about the problem.
1) Use LIKE to and compare the strings but you actually have to build strings a little oddly to do it:
SELECT *
FROM
#Table1 t1
WHERE
NOT EXISTS (SELECT *
FROM #Table2 t2
WHERE ',' + t2.clm02 + ',' LIKE '%,' + CAST(t1.clm01 AS VARCHAR(15)) + ',%')
What you see is ,1,2,3, is like %,clm01value,% you must add the delimiter to the strings for this to work properly and you have to cast/convert clm01 to a char datatype. There are drawbacks to this solution but if your data sets are straight forward it could work for you.
2) Split the comma delimited string to rows and then use a left join, not exists, or not in. here is a method to convert your csv to xml and then split
;WITH cteClm02Split AS (
SELECT
clm02
FROM
(SELECT
CAST('<X>' + REPLACE(clm02,',','</X><X>') + '</X>' AS XML) as xclm02
FROM
#Table2) t
CROSS APPLY (SELECT t.n.value('.','INT') clm02
FROM
t.xclm02.nodes('X') as t(n)) ca
)
SELECT t1.*
FROM
#Table1 t1
LEFT JOIN cteClm02Split t2
ON t1.clm01 = t2.clm02
WHERE
t2.clm02 IS NULL
OR use NOT EXISTS with same cte
SELECT t1.*
FROM
#Table1 t1
WHERE
NOT EXISTS (SELECT * FROM cteClm02Split t2 WHERE t1.clm01 = t2.clm02)
There are dozens of other ways to split delimited strings and you can choose whatever way works for you.
Note: I am not showing IN/NOT IN as an answer because I don't recommend the use of it. If you do use it make sure that you are never comparing a NULL in the select etc. Here is another good post concerning performance etc. NOT IN vs NOT EXISTS
here are the table variables that were used:
DECLARE #Table1 AS TABLE (clm01 INT)
DECLARE #Table2 AS TABLE (clm02 VARCHAR(15))
INSERT INTO #Table1 VALUES (1),(2),(3),(4),(5)
INSERT INTO #Table2 VALUES ('1,2,3')
Help! Here is a very simple a,b,c sample of what I need to accomplish. I have been pulling my hair out. I've written this before but can't get my head around it now! So here it is, with actual and expected results demonstrated below:
set nocount on
declare #a table (id int, a varchar(10))
declare #b table (ref int, b varchar(10), c varchar(20))
insert into #a select 1, 'bingo'
insert into #a select 2, 'bongo'
insert into #b select 1, 'T5', 'asdfwef'
insert into #b select 1, 'T8', 'asfqwez'
insert into #b select 1, 'T6', 'qweoae'
insert into #b select 1, 'T8', 'qzoeqe'
insert into #b select 1, 'T9', 'oqeizef'
insert into #b select 2, 'T3', 'awega'
insert into #b select 2, 'T6', 'fhaeaw'
insert into #b select 2, 'T3', 'fqsegw'
select * from #a a join #b b on a.id = b.ref
-- Expected (Uniqueness is: a’s id to b’s ref and the first b value ingoring b’s c value)
----1,bingo,1,T5,asdfwef
----1,bingo,1,T8,asfqwez
----1,bingo,1,T6,qweoae
----1,bingo,1,T9,oqeizef
----2,bongo,2,T3,awega
----2,bongo,2,T6,fhaeaw
-- Actual
----1,bingo,1,T5,asdfwef
----1,bingo,1,T8,asfqwez
----1,bingo,1,T6,qweoae
----1,bingo,1,T8,qzoeqe
----1,bingo,1,T9,oqeizef
----2,bongo,2,T3,awega
----2,bongo,2,T6,fhaeaw
----2,bongo,2,T3,fqsegw
Your query is returning the correct results. All the matching values from #b.
If you want the first b value, you need to do two things. First, you need to include an ordering column in b so you know what "first" is. Remember, SQL tables are unordered. This is easy:
declare #b table (id int identity(1,1) not null, ref int, b varchar(10), c varchar(20));
You then have to change the inserts to insert all but the id:
insert into #b(ref, b, c) select 1, 'T5', 'asdfwef';
Now you are ready for the actual query:
select *
from #a a join
(select b.*, row_number() over (partition by b.ref, b.b order by b.id) as seqnum
from #b b
) b
on a.id = b.ref and b.seqnum = 1