I have a big table with data like this:
ID Title
-- ------------------------
1 01_SOMESTRING_038
2 01_SOMESTRING K5038
3 01_SOMESTRING-648
4 K-OTHERSTRING_T_73474
5 K-OTHERSTRING_T_ffk
6 ABC
7 DEF
And the task is now to find similarities in that column, and write that found similarity to a new column.
So the desired output would be like this:
ID Title Similarity
-- ------------------------ -----------------
1 01_SOMESTRING_038 01_SOMESTRING
2 01_SOMESTRING K5038 01_SOMESTRING
3 01_SOMESTRING-648 01_SOMESTRING
4 K-OTHERSTRING_T_73474 K-OTHERSTRING_T_
5 K-OTHERSTRING_T_ffk K-OTHERSTRING_T_
6 ABC NULL
7 DEF NULL
How can I achieve that in MS SQL Server 17?
Any help is much appreciated. Thanks!
EDIT: The strings are not only broken by delimiters such as "-", "_".
And for handling competeing similrities I would set a minimum length for the similarity. For instance 10.
Try the following, using a recursive CTE to split out the letters, then we can group them up to find the greatest match:
WITH TITLE_EXPAND AS (
SELECT
1 MatchLen
,CAST(SUBSTRING(Title,1,1) as NVARCHAR(255)) MatchString
,Title
,ID
FROM
[SourceDataTable]
UNION ALL
SELECT
MatchLen + 1
,CAST(SUBSTRING(Title,1,MatchLen+1) AS NVARCHAR(255))
,Title
,ID
FROM
TITLE_EXPAND
WHERE
MatchLen < LEN(Title)
)
SELECT DISTINCT
SDT.ID
,SDT.title
,FIRST_VALUE(MatchString) OVER (PARTITION BY SDT.ID ORDER BY SC.MatchLen DESC, SC.MatchCount DESC) Similarity
FROM
[SourceDataTable] SDT
LEFT JOIN
(SELECT
*
,COUNT(*) OVER (PARTITION BY MatchString, MatchLen) MatchCount
FROM
TITLE_EXPAND) SC
ON
SDT.ID = SC.ID
AND
SC.MatchCount > 1
ORDER BY SDT.ID
Where SourceDataTable is your source table. The Similarity value will be the longest matched similar value.
Related
I looked at other examples, but I don't know enough about SQL to adapt it to my needs. I have a table that looks like this:
ID Month NAME COUNT First LAST TOTAL
------------------------------------------------------
1 JAN2013 fred 4
2 MAR2013 fred 5
3 APR2014 fred 1
4 JAN2013 Tom 6
5 MAR2014 Tom 1
6 APR2014 Tom 1
This could be in separate queries, but I need 'First' to equal the first month that a particular name is used, so every row with fred would have JAN2013 in the first field for example. I need the 'Last" column to equal the month of the last record of each name, and finally I need the 'total' column to be the sum of all the counts for each name, so in each row that had fred the total would be 10 in this sample data. This is over my head. Can one of you assist?
This is crude but should do the trick. I renamed your fields a bit because you are using a bunch of "RESERVED" sql words and that is bad form.
;WITH cte as
(
Select
[NAME]
,[nmCOUNT]
,ROW_NUMBER() over (partition by NAME order by txtMONTH ASC) as 'FirstMonth'
,ROW_NUMBER() over (partition by NAME order by txtMONTH DESC) as 'LastMonth'
,SUM([nmCOUNT]) as 'TotNameCount'
From Table
Group by NAME, [nmCOUNT]
)
,cteFirst as
(
Select
NAME
,[nmCOUNT]
,[TotNameCount]
,[txtMONTH] as 'ansFirst'
From cte
Where FirstMonth = 1
)
,cteLast as
(
Select
NAME
,[txtMONTH] as 'ansLast'
From cte
Where LastMonth = 1
Select c.NAME, c.nmCount, c.ansFirst, l.ansLast, c.TotNameCount
From cteFirst c
LEFT JOIN cteLast l on c.NAME = l.NAME
I am dealing with a poorly designed database column which has values like this
ID cid Score
1 1 3 out of 3
2 1 1 out of 5
3 2 3 out of 6
4 3 7 out of 10
I want the aggregate sum and percentage of Score column grouped on cid like this
cid sum percentage
1 4 out of 8 50
2 3 out of 6 50
3 7 out of 10 70
How do I do this?
You can try this way :
select
t.cid
, cast(sum(s.a) as varchar(5)) +
' out of ' +
cast(sum(s.b) as varchar(5)) as sum
, ((cast(sum(s.a) as decimal))/sum(s.b))*100 as percentage
from MyTable t
inner join
(select
id
, cast(substring(score,0,2) as Int) a
, cast(substring(score,charindex('out of', score)+7,len(score)) as int) b
from MyTable
) s on s.id = t.id
group by t.cid
[SQLFiddle Demo]
Redesign the table, but on-the-fly as a CTE. Here's a solution that's not as short as you could make it, but that takes advantage of the handy SQL Server function PARSENAME. You may need to tweak the percentage calculation if you want to truncate rather than round, or if you want it to be a decimal value, not an int.
In this or most any solution, you have to count on the column values for Score to be in the very specific format you show. If you have the slightest doubt, you should run some other checks so you don't miss or misinterpret anything.
with
P(ID, cid, Score2Parse) as (
select
ID,
cid,
replace(Score,space(1),'.')
from scores
),
S(ID,cid,pts,tot) as (
select
ID,
cid,
cast(parsename(Score2Parse,4) as int),
cast(parsename(Score2Parse,1) as int)
from P
)
select
cid, cast(round(100e0*sum(pts)/sum(tot),0) as int) as percentage
from S
group by cid;
I am new to Oracle. I have an Oracle table with three columns: serialno, item_category and item_status. In the third column the rows have values of serviceable, under_repair or condemned.
I want to run the query using count to show how many are serviceable, how many are under repair, how many are condemned against each item category.
I would like to run something like:
select item_category
, count(......) "total"
, count (.....) "serviceable"
, count(.....)"under_repair"
, count(....) "condemned"
from my_table
group by item_category ......
I am unable to run the inner query inside the count.
Here's what I'd like the result set to look like:
item_category total serviceable under repair condemned
============= ===== ============ ============ ===========
chair 18 10 5 3
table 12 6 3 3
You can either use CASE or DECODE statement inside the COUNT function.
SELECT item_category,
COUNT (*) total,
COUNT (DECODE (item_status, 'serviceable', 1)) AS serviceable,
COUNT (DECODE (item_status, 'under_repair', 1)) AS under_repair,
COUNT (DECODE (item_status, 'condemned', 1)) AS condemned
FROM mytable
GROUP BY item_category;
Output:
ITEM_CATEGORY TOTAL SERVICEABLE UNDER_REPAIR CONDEMNED
----------------------------------------------------------------
chair 5 1 2 2
table 5 3 1 1
This is a very basic "group by" query. If you search for that you will find plenty of documentation on how it is used.
For your specific case, you want:
select item_category, item_status, count(*)
from <your table>
group by item_category, item_status;
You'll get something like this:
item_category item_status count(*)
======================================
Chair under_repair 7
Chair condemned 16
Table under_repair 3
Change the column ordering as needed for your purpose
I have a tendency of writing this stuff up so when I forget how to do it, I have an easy to find example.
The PIVOT clause was new in 11g. Since that was 5+ years ago, I'm hoping you are using it.
Sample Data
create table t
(
serialno number(2,0),
item_category varchar2(30),
item_status varchar2(20)
);
insert into t ( serialno, item_category, item_status )
select
rownum serialno,
( case
when rownum <= 12 then 'table'
else 'chair'
end ) item_category,
( case
--table status
when rownum <= 12
and rownum <= 6
then 'servicable'
when rownum <= 12
and rownum between 7 and 9
then 'under_repair'
when rownum <= 12
and rownum > 9
then 'condemned'
--chair status
when rownum > 12
and rownum < 13 + 10
then 'servicable'
when rownum > 12
and rownum between 23 and 27
then 'under_repair'
when rownum > 12
and rownum > 27
then 'condemned'
end ) item_status
from
dual connect by level <= 30;
commit;
and the PIVOT query:
select *
from
(
select
item_status stat,
item_category,
item_status
from t
)
pivot
(
count( item_status )
for stat in ( 'servicable' as "servicable", 'under_repair' as "under_repair", 'condemned' as "condemned" )
);
ITEM_CATEGORY servicable under_repair condemned
------------- ---------- ------------ ----------
chair 10 5 3
table 6 3 3
I still prefer #Ramblin' Man's way of doing it (except using CASE in place of DECODE) though.
Edit
Just realized I left out the TOTAL column. I'm not sure there's a way to get that column using the PIVOT clause, perhaps someone else knows how. May also be the reason I don't use it that often.
Suppose I have a table:
HH SLOT RN
--------------
1 1 null
1 2 null
1 3 null
--------------
2 1 null
2 2 null
2 3 null
I want to set RN to be a random number between 1 and 10. It's ok for the number to repeat across the entire table, but it's bad to repeat the number within any given HH. E.g.,:
HH SLOT RN_GOOD RN_BAD
--------------------------
1 1 9 3
1 2 4 8
1 3 7 3 <--!!!
--------------------------
2 1 2 1
2 2 4 6
2 3 9 4
This is on Netezza if it makes any difference. This one's being a real headscratcher for me. Thanks in advance!
To get a random number between 1 and the number of rows in the hh, you can use:
select hh, slot, row_number() over (partition by hh order by random()) as rn
from t;
The larger range of values is a bit more challenging. The following calculates a table (called randoms) with numbers and a random position in the same range. It then uses slot to index into the position and pull the random number from the randoms table:
with nums as (
select 1 as n union all select 2 union all select 3 union all select 4 union all select 5 union all
select 6 union all select 7 union all select 8 union all select 9
),
randoms as (
select n, row_number() over (order by random()) as pos
from nums
)
select t.hh, t.slot, hnum.n
from (select hh, randoms.n, randoms.pos
from (select distinct hh
from t
) t cross join
randoms
) hnum join
t
on t.hh = hnum.hh and
t.slot = hnum.pos;
Here is a SQLFiddle that demonstrates this in Postgres, which I assume is close enough to Netezza to have matching syntax.
I am not an expert on SQL, but probably do something like this:
Initialize a counter CNT=1
Create a table such that you sample 1 row randomly from each group and a count of null RN, say C_NULL_RN.
With probability C_NULL_RN/(10-CNT+1) for each row, assign CNT as RN
Increment CNT and go to step 2
Well, I couldn't get a slick solution, so I did a hack:
Created a new integer field called rand_inst.
Assign a random number to each empty slot.
Update rand_inst to be the instance number of that random number within this household. E.g., if I get two 3's, then the second 3 will have rand_inst set to 2.
Update the table to assign a different random number anywhere that rand_inst>1.
Repeat assignment and update until we converge on a solution.
Here's what it looks like. Too lazy to anonymise it, so the names are a little different from my original post:
/* Iterative hack to fill 6 slots with a random number between 1 and 13.
A random number *must not* repeat within a household_id.
*/
update c3_lalfinal a
set a.rand_inst = b.rnum
from (
select household_id
,slot_nbr
,row_number() over (partition by household_id,rnd order by null) as rnum
from c3_lalfinal
) b
where a.household_id = b.household_id
and a.slot_nbr = b.slot_nbr
;
update c3_lalfinal
set rnd = CAST(0.5 + random() * (13-1+1) as INT)
where rand_inst>1
;
/* Repeat until this query returns 0: */
select count(*) from (
select household_id from c3_lalfinal group by 1 having count(distinct(rnd)) <> 6
) x
;
Correction to my question....
I'm trying to select and sort in a query from a single table. The primary key for the table is a combination of a serialized number and a time/date stamp.
The table's name in the database is "A12", the columns are defined as:
Serial2D (PK, char(25), not null)
Completed (PK, datetime, not null)
Result (smallint, null)
MachineID (FK, smallint, null)
PT_1 (float, null)
PT_2 (float, null)
PT_3 (float, null)
PT_4 (float, null)
Since the primary key for the table is a combination of the "Serial2D" and "Completed", there can be multiple "Serial2D" entries with different values in the "Completed" and "Result" columns. (I did not make this database... I have to work with what I got)
I want to write a query that will utilize the value of the "Result" column ( always a "0" or "1") and retrive only unique rows for each "Serial2D" value. If the "Result" column has a "1" for that row, I want to choose it over any entries with that Serial that has a "0" in the Result column. There should be only one entry in the table that has a Result column entry of "1" for any Serial2D value.
Ex. table
Serial2d Completed Result PT_1 PT_2 PT_3 PT_4
------- ------- ------ ---- ---- ---- ----
A1 1:00AM 0 32.5 20 26 29
A1 1:02AM 0 32.5 10 29 40
A1 1:03AM 1 10 5 4 3
B1 1:04AM 0 29 4 1 9
B1 1:05AM 0 40 3 4 9
C1 1:06AM 1 9 7 6 4
I would like to be able to retrieve would be:
Serial2d Completed Result PT_1 PT_2 PT_3 PT_4
------- ------- ------ ---- ---- ---- ----
A1 1:03AM 1 10 5 4 3
B1 1:05AM 0 40 3 4 9
C1 1:06AM 1 9 7 6 4
I'm new to SQL and I'm still learning ALL the syntax. I'm finding it difficult to search for the correct operators to use since I'm not sure what I need, so please forgive my ignorance. A post with my answer could be staring me right in the face and i wouldn't know it, please just point me to it.
I appreciate the answers to my previous post, but the answers weren't sufficient for me due to MY lack of information and ineptness with SQL. I know this is probably insanely easy for some, but try to remember when you first started SQL... that's where I'm at.
Since you are using SQL Server, you can use Windowing Functions to get this data.
Using a sub-query:
select *
from
(
select *,
row_number() over(partition by serial2d
order by result desc, completed desc) rn
from a12
) x
where rn = 1
See SQL Fiddle with Demo
Or you can use CTE for this query:
;with cte as
(
select *,
row_number() over(partition by serial2d
order by result desc, completed desc) rn
from a12
)
select *
from cte c
where rn = 1;
See SQL Fiddle With Demo
You can group by Serial to get the MAX of each Time.
SELECT Serial, MAX([Time]) AS [Time]
FROM myTable
GROUP BY Serial
HAVING MAX(Result) => 0
SELECT
t.Serial,
max_Result,
MAX([time]) AS max_time
FROM
myTable t inner join
(SELECT
Serial,
MAX([Result]) AS max_Result
FROM
myTable
GROUP BY
Serial) m on
t.serial = m.serial and
t.result = m.max_result
group by
t.serial,
max_Result
This can be solved using a correlated sub-query:
SELECT
T.serial,
T.[time],
0 AS result
FROM tablename T
WHERE
T.result = 1
OR
NOT EXISTS(
SELECT 1
FROM tablename
WHERE
serial = T.serial
AND (
[time] > T.[time]
OR
result = 1
)
)