trying desperately to combine 2 simple answers into specifically what i need.
sql loop and set properties
sql to set an xml value
SET #I := 0;
SELECT *,
#I := #I + 1
SET xml = UpdateXML(xml,'comic/pageNumber', '<pageNumber>'.#I.'</pageNumber>')
FROM `comics`
ORDER BY ExtractValue(xml,'comic/pageNumber')+100000 ASC
this is as close as i have come, i know the SELECT / ORDER BY works separate from trying to SET the xml property.
side note: the +100000 is a work
around to treat the value as numeric
for sorting. otherwise 11 < 2 but
100011 > 100002
i have also tried this
SET #I := 0;
UPDATE comics,
#I := #I + 1 AS newPageNumber
SET xml = UpdateXML(xml,'comic/pageNumber', '<pageNumber>'.#I.'</pageNumber>')
WHERE 1
ORDER BY ExtractValue(xml,'comic/pageNumber')+100000 ASC
i think i just don't know how to combine the SELECT and UPDATE
UPDATE comics
inner join (
select c.id, #row:=#row+1 rownum
from (select #row:=0) X cross join comics c
ORDER BY ExtractValue(xml,'comic/pageNumber')*1.0) Y on Y.id=comics.id
SET xml = UpdateXML(xml,
'comic/pageNumber',
concat('<pageNumber>',Y.rownum,'</pageNumber>'))
;
Based on this test schema and data
create table comics (id int auto_increment primary key, xml text);
insert comics select null, '<comic><name>test1</name><pageNumber>7</pageNumber><content>page 5 con</content></comic>';
insert comics select null, '<comic><name>test1</name><pageNumber>3</pageNumber><content>page 6 con</content></comic>';
insert comics select null, '<comic><name>test1</name><pageNumber>5</pageNumber><content>page 7 con</content></comic>';
Related
I have a table with the following data:
Part Comp level item_nbr
-------------------------------
abc ab 1 1
null cd 2 2
null ef 3 3
cde gh 1 4
null ij 2 5
null kl 3 6
null mn 4 7
I would like to update the nulls to the value in each level 1, so every level that is >1 is updated with the level one value.
Part Comp level
---------------------
abc ab 1
abc cd 2
abc ef 3
cde gh 1
cde ij 2
cde kl 3
cde mn 4
I am at a loss as to how to achieve this on a very large dataset. Any help would be greatly appreciated!
To explain another way,
part level
abc 1
2
3
Then the next row is populated with another part
efg 1
2
2
etc.
Further clarification:
I need the string"abc" to be filled down with the string "abc" while the column fields below are null. The next row has a string of efg and the following column fields below are null, again, those fields should be filled down with the value "efg" and so on.
The level field = 1 will always have a part number, but all the other levels report up to the level 1 part, so should be populated identically. And repeat.
Hope this makes sense.
Use an updatable CTE with window functions:
with toupdate as (
select t.*,
max(part) over (partition by itm_nbr_not_null) as new_part
from (select t.*,
max(case when part is not null then item_nbr end) over (order by item_nbr) as itm_nbr_not_null
from t
) t
)
update toupdate
set part = new_part
where part is null;
You can run the CTE to see what is happening.
well, from your question what I understand is, you need to update the null column's value until you get a not null value. and you want to continue it up to the last row of the table.
for that scenario, I created a stored procedure, where I read the value of every n-th cell if it is null I changing it with the prev. cell's value, when the cell was not null.
Approach:
create a temporary table/ table variable.
add an extra column, which is basically identity, which will help to rank the column.
iterate a loop until the maximum row is reached.
in each iteration, read the cell value for the i-th row
4.1 if it is not null put it in a temporary variable.
4.2 else, replace/update the i-th cell's value with the temporary variable
continue it, until you reached up to the last row of the table/table variable.
look at my following snippets:
create proc DemoPost
as
begin
declare #table table(serial_no int identity(1,1), name varchar(30), text varchar(30), level int)
insert #table
select Name, Text, Level from Demo
declare #max as int = (select max(serial_no) from #table)
--select #max
declare #i as int =0
declare #temp as varchar(30)
declare #text as varchar(30)
while #i < #max
begin
set #i = #i +1
set #temp = (select name from #table where serial_no = #i)
-- if #temp is not null, fetch its value, otherwise, update/replace it with
-- previously gotten not-null cell's value.
if #temp is not null
begin
set #text = (select name from #table where serial_no = #i)
end
else
begin
update #table
set name = #text where serial_no = #i
end
end
select name, text, level from #table
end
You can update it using temporary table according to the given scenario i thought item_nbr is unique in row Hope this will help
SELECT *
INTO #TEMP
FROM URTablehere
DECLARE #PRev VARCHAR(MAX)
WHILE ( SELECT COUNT(*)
FROM URTablehere
) > 0
BEGIN
DECLARE #ID INT
DECLARE #Part VARCHAR(MAX)
DECLARE #Num INT
SELECT TOP ( 1 )
#ID = level ,
#Part = Part ,
#Num = item_nbr
FROM #TEMP
IF ( #ID = 1 )
BEGIN
SELECT #PRev = #Part
END
IF ( #ID > 1
AND #Part IS NULL
)
BEGIN
UPDATE URTablehere
SET Part = #PRev
WHERE item_nbr = #Num
END
DELETE
FROM #TEMP WHERE item_nbr=#Num
END
could someone please help? My starting table looks like this with 2 fields:
Name Counter
dave 2
Joe 3
I want my result to look like this:
Name Counter
dave 1
dave 2
joe 1
joe 2
joe 3
Essentially creating n number of records base on the counter and starts at 1. I tried to do a loop using counter as a variable, but the code just runs nonstop.. could someone help?
A procedural SQL Server solution:
declare #input table
(
name nvarchar(100)
,wantedrows int
,processed bit
,id uniqueidentifier
);
declare #output table
(
name nvarchar(100)
,rownum int
);
insert into #input
select 'Dave',3,0,newid()
union
select 'Joe',2,0,newid();
while exists(select * from #input where processed = 0)
begin
declare #currentid uniqueidentifier = (select top 1 id from #input where processed = 0);
declare #currentwantedrows int = (select wantedrows from #input where id = #currentid);
declare #i int = 0;
while #i < #currentwantedrows
begin
insert into #output
select name,#i+1
from #input
where id = #currentid;
set #i = #i + 1;
end;
update #input set processed = 1 where id = #currentid;
end
select name,wantedrows from #input;
select * from #output;
You can use a number-table or following trick using a system view to build a sequence:
WITH Nums AS
(
SELECT n = ROW_NUMBER() OVER (ORDER BY [object_id])
FROM sys.all_objects
)
SELECT Name, Counter = n
FROM Nums n CROSS JOIN Table1 t1
WHERE n BETWEEN 1 AND Counter
ORDER BY Name, Counter;
Demo
This view has only about 2000 rows, so if you need more you could use a number-table.
http://sqlperformance.com/2013/01/t-sql-queries/generate-a-set-1
( presuming SQL-Server )
Is a hundred copies enough?
create table #c (num)
insert into #c (num)
select 0 union
select 1 union
select 2 union
select 3 union
select 4 union
select 5 union
select 6 union
select 7 union
select 8 union
select 9
select T.Name, c1.num * 10 + c0.num + 1
from T, #c c1, #c c0
where c1.num * 10 + c0.num < T.Counter
drop table #c
You didn't say which version of Sybase. The old ones I've worked on didn't allow derived tables so I had to throw the values into a temp table. But you can see how to extend the idea. This may not be the best approach if this is something you need to do more than once though.
I have a table which is already truncated (Microsoft SQL 2008). I have to now populate it with sequential numbers up to 50,000 records arbitrary numbers (doesn't mater) up to 7 characters.
Can any one help as to what SQL statement I need to write that will automatically populate the newly empty table with A000001,A0000002,A0000003, etc so that I can sort number the records within the table.
I have approximately 50000 records which I need to sequentially entered and I really don't want to number the column manually via hand editing.
Thanks in advance.
I'd use excel to generate your unique ids using the following:
In A column:
=CONCATENATE($C2, TEXT($B2,"000000"))
In B column put a 1 in the first row and the following code in all subsequent rows:
=SUM($B4 + 1)
In C column:
The letter A
Then just import the excel csv as a table and you'll have all your ids ready to insert into your empty table.
The SQL below loads a table variable up. Just select from it and insert the data into the new table. Certainly not the model of efficiency, but it'll get the job done.
DECLARE #tmp TABLE(
Value NVARCHAR(10)
)
DECLARE #Counter INT=0
DECLARE #Padding NVARCHAR(20)
WHILE #Counter<50000
BEGIN
SET #Counter=#Counter+1
SET #Padding=
CASE LEN(CONVERT(NVARCHAR,#Counter))
WHEN 1 THEN '00000'
WHEN 2 THEN '0000'
WHEN 3 THEN '000'
WHEN 4 THEN '00'
WHEN 5 THEN '0'
ELSE ''
END
INSERT INTO #tmp SELECT 'A' + #Padding + CONVERT(NVARCHAR,#Counter)
END
select * from #tmp
Use Stacked CTE to generate sequential Numbers
;WITH e1(n) AS
(
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
), -- 10
e2(n) AS (SELECT 1 FROM e1 CROSS JOIN e1 AS b), -- 10*10
e3(n) AS (SELECT 1 FROM e2 CROSS JOIN e2 AS b), -- 100*100
e4(n) AS (SELECT 1 FROM e3 CROSS JOIN (SELECT TOP 5 n FROM e1) AS b) -- 5*10000
SELECT n = 'A'+right('000000'+
convert(varchar(20),ROW_NUMBER() OVER (ORDER BY n)),7)
FROM e4 ORDER BY n;
Check here for more methods to generate sequential numbers with performance analysis
Use a table with an identity column and populate it. Then update that table to set the alpha value you need as follows:
create table MyTable (
ID int not null identity(1,1),
Alpha varchar(30)
)
truncate table MyTable
begin tran -- makes it run much faster
declare #i int
select #i = 1
while #i < 1000000
begin
insert into MyTable (Alpha) values ('')
select #i = #i + 1
end
commit
update MyTable set Alpha = 'A' + replicate('0', 6 - len(cast(ID as varchar(30)))) + cast(ID as varchar(30))
I sure hope someone can help me out with this issue. I have been searching for hours to find it but I am coming up empty.
In this example I have two columns in my table
GRP_ID Desc
My group ID is the way I will identify that these products are of the same type, and desc is what I want to find all the common words.
So here is my table
GRP_ID Desc
-------------------------------
2 Red Hat
2 Green Hat
2 Yellow Hat
3 Boots Large Brown
3 Boots Medium Red
3 Boots Medium Brown
What I want as a result of the query would be the following
GRP_ID Desc
-----------------------
2 Hat
3 Boots
So what I want is all the words that appear in every string in the group or the common words in the group.
I think you'd need to create a mapping table for GRP_ID and products - e.g. Hat and Boots.
CREATE TABLE GroupProductMapping (
GRP_ID INT NOT NULL, -- I'm assuming its an Int
ProductDesc VARCHAR(50) NOT NULL
)
SELECT a.GRP_ID,
b.ProductDesc Desc
FROM {Table_Name} a
INNER JOIN GroupProductMapping b ON a.GRP_ID = b.GRP_ID
Alternatively, if you don't have too many products. You could use CASE in your SELECT clause.
e.g.
SELECT
GRP_ID,
CASE GRP_ID
WHEN 1 THEN 'Hat'
WHEN 2 THEN 'Boots'
END AS Desc
FROM {Table_Name}
{Table_Name} is the name of your original table.
Ideally you would normalise your data and store the words in a separate table.
However for your immediate requirements, you first need to provide a UDF to split 'desc' into words. I poached this function:
-- this function splits the provided strings on a delimiter
-- similar to .Net string.Split.
-- I'm sure there are alternatives (such as calling string.Split through
-- a CLR function).
CREATE FUNCTION [dbo].[Split]
(
#RowData NVARCHAR(MAX),
#Delimeter NVARCHAR(MAX)
)
RETURNS #RtnValue TABLE
(
ID INT IDENTITY(1,1),
Data NVARCHAR(MAX)
)
AS
BEGIN
DECLARE #Iterator INT
SET #Iterator = 1
DECLARE #FoundIndex INT
SET #FoundIndex = CHARINDEX(#Delimeter,#RowData)
WHILE (#FoundIndex>0)
BEGIN
INSERT INTO #RtnValue (data)
SELECT
Data = LTRIM(RTRIM(SUBSTRING(#RowData, 1, #FoundIndex - 1)))
SET #RowData = SUBSTRING(#RowData,
#FoundIndex + DATALENGTH(#Delimeter) / 2,
LEN(#RowData))
SET #Iterator = #Iterator + 1
SET #FoundIndex = CHARINDEX(#Delimeter, #RowData)
END
INSERT INTO #RtnValue (Data)
SELECT Data = LTRIM(RTRIM(#RowData))
RETURN
END
Then you need to split the descriptions and do some grouping (which you would also do if the data was normalised)
-- get the count of each grp_id
with group_count as
(
select grp_id, count(*) cnt from [Group]
group by grp_id
),
-- get the count of each word in each grp_id
group_word_count as
(
select count(*) cnt, grp_id, data from
(
select * from [group] g
cross apply dbo.Split(g.[Desc], ' ')
)
t
group by grp_id, data
)
-- return rows where number of grp_id = number of words in grp_id
select gwc.GRP_ID, gwc.Data [Desc] from group_word_count gwc
inner join group_count gc on gwc.GRP_ID = gc.GRP_ID and gwc.cnt = gc.cnt
Where [Group] is your table.
I have two tables where the data is not related
For each row in table A i want e.g. 3 random rows in table B
This is fairly easy using a cursor, but it is awfully slow
So how can i express this in single statement to avoid RBAR ?
To get a random number between 0 and (N-1), you can use.
abs(checksum(newid())) % N
Which means to get positive values 1-N, you use
1 + abs(checksum(newid())) % N
Note: RAND() doesn't work - it is evaluated once per query batch and you get stuck with the same value for all rows of tableA.
The query:
SELECT *
FROM tableA A
JOIN (select *, rn=row_number() over (order by newid())
from tableB) B ON B.rn <= 1 + abs(checksum(newid())) % 9
(assuming you wanted up to 9 random rows of B per A)
assuming tableB has integer surrogate key, try
Declare #maxRecs integer = 11 -- Maximum number of b records per a record
Select a.*, b.*
From tableA a Join tableB b
On b.PKColumn % (floor(Rand() * #maxRecs)) = 0
If you have a fixed number that you know in advance (such as 3), then:
select a.*, b.*
from a cross join
(select top 3 * from b) b
If you want a random number of rows from "b" for each row in "a", the problem is a bit harder in SQL Server.
Heres an example of how this could be done, code is self contained, copy and press F5 ;)
-- create two tables we can join
DECLARE #datatable TABLE(ID INT)
DECLARE #randomtable TABLE(ID INT)
-- add some dummy data
DECLARE #i INT = 1
WHILE(#i < 3) BEGIN
INSERT INTO #datatable (ID) VALUES (#i)
SET #i = #i + 1
END
SET #i = 1
WHILE(#i < 100) BEGIN
INSERT INTO #randomtable (ID) VALUES (#i)
SET #i = #i + 1
END
--The key here being the ORDER BY newid() which makes sure that
--the TOP 3 is different every time
SELECT
d.ID AS DataID
,rtable.ID RandomRow
FROM #datatable d
LEFT JOIN (SELECT TOP 3 * FROM #randomtable ORDER BY newid()) as rtable ON 1 = 1
Heres an example of the output