I'm using MySQL to try to manipulate some data for cancer research and machine learning. It seems an ideal problem for the PIVOT statement but I can't quite get it to work and would welcome any help. If there's a better tool, like maybe R, I'm all ears too.
Let's say I have three tables, patients, samples, and mutations:
patients table has unique rows, each with a unique patient_id.
samples table has unique rows, each with a unique sample_id, but also a patient_id that can be found in the patients table. There may be multiple rows in the samples table with the same patient_id.
mutations table has NON-unique rows. Each row in the mutations table contains just two columns: gene and sample_id.
I need to create a new table, call it summary, with patient_id in the first column, sample_id, followed by a column for every distinct gene in the mutations table.
Each row of the new summary table should contain
the patient_id from the patients table,
the sample_id from the samples table,
a the number 1 in each following gene column for each gene in the mutations table that has a sample_id for the specific patient or a number 0 if not.
New summary table looks sort of like this:
patient_id sample_id gene A gene B gene C gene D etc
12345678 54321 1 0 0 0
23456789 65432 0 1 1 0
34567890 76543 0 0 1 0
34567890 87654 0 1 0 1
etc
The new summary table must have an entry, either a 0 or a 1, for every distinct gene found in the mutations table even if there are no entries in the mutations table that have a sample_id belonging to the patient for a specific row.
Remember, there may be multiple samples belonging to the same patient, so the summary table could contain multiple rows for a given patient - each row for a different sample.
Here's my current non-working SQL:
SELECT cs.patient_id, g.*
FROM samples cs
INNER JOIN (
SELECT *
FROM
(WITH cp AS
(SELECT * FROM
(SELECT gene FROM mutations GROUP BY gene) c
CROSS JOIN (SELECT sample_id FROM samples GROUP BY sample_id) m)
SELECT cp.gene, cp.sample_id, IFNULL(m.id,0) id
FROM cp
LEFT JOIN (SELECT gene, sample_id, 1 id FROM mutations) m on m.gene=cp.gene and m.sample_id=cp.sample_id)
PIVOT ( MAX(id) for gene in ('BAP1','PDGFRA','KRAS','CDKN1B','IDH1','ARID1A','DOT1L','NOTCH4','ABL1',
'PBRM1','MLL3','TET2','SPEN','CCND2','DDR2','RICTOR','SMAD4','GLI1','RASA1',
'MAP2K1','CSF3R','HIST1H3D','DNMT3B','CEBPA','GATA2','ARID1B','BRCA2','EPHA7',
'CTNNB1','EPHA5','EP300','RAF1','NF1','EGFR','NBN','INHA','CARD11','ANKRD11',
'ERBB3','TERT','DNMT1','ATM','RIT1','PDCD1','SMARCA4','FOXP1','DICER1','TGFBR2',
'PTPRS','FANCC','APC','NCOA3','NTRK1','PTPRD','NSD1','GRIN2A','SMARCB1','PTCH1',
'KEAP1','KDR','IRS2','PIK3R3','SUFU','STAG2','MAP3K13','SOX9','SETD2','FAT1',
'ZFHX3','NRAS','MAP3K1','ERBB4','JAK3','NF2','PGR','KDM6A','RPTOR','TP53','CIC',
'MSH2','MAP2K4','AXIN2','PTEN','XPO1','ERCC4','AXL','RNF43','DNMT3A','ERG','NOTCH2',
'RFWD2','IGF1R','GATA1','SMAD3','TMPRSS2','MLL','BRAF','TET1','BCOR','YAP1','HLA-A',
'PLCG2','CBL','IRS1','PIK3CA','POLE','LATS2','MST1','H3F3B','IRF4','AR','B2M','NCOR1',
'FUBP1','NOTCH3','ATR','RPS6KB2','TSC2','PIK3CG','MDM2','ROS1','TCF3','TSC1','FGFR2',
'FBXW7','FOXA1','MEN1','CDKN2Ap16INK4A','EPHA3','PMS1','PAK1','E2F3','PIK3CD','PLK2',
'MPL','RHEB','RBM10','ASXL2','MSH6','RAD21','BRIP1','PTPRT','GNA11','CDKN1A','RAD50',
'BRD4','STK11','ARID2','RUNX1','MTOR','JAK1','TBX3','MALT1','RYBP','MLL2','PIK3CB',
'SMO','AXIN1','MAPK3','VHL','JUN','KDM5A','ARID5B','AMER1','PPM1D','ASXL1','MLH1',
'CASP8','BARD1','DAXX','CDH1','PALB2','AKT3','RECQL4','IGF2','MED12','FLT3','HIST3H3',
'MST1R','EIF4A2','CREBBP','STAT5B','PHOX2B','BRCA1','ERBB2','MITF','RB1','CD79A',
'TMEM127','MAPK1','CDKN2A','CDKN2Ap14ARF','CSF1R','FLT4','CENPA','RPS6KA4','SRC',
'ERCC3','NEGR1','RET','ACVR1','SYK','ICOSLG','FYN','SOX17','ETV6','NTRK3','HIST1H1C',
'IDH2','CHEK1','GNAS','PPP6C','EZH2','MYCL1','SDHA','MDC1','ARAF','RAC1','KDM5C','PARP1',
'NKX2-1','CXCR4','SMAD2','IL7R','TGFBR1','U2AF1','SF3B1','FGFR4','ERRFI1','SMARCD1','FGFR1',
'EPHB1','PDPK1','FLCN','RAD54L','MGA','PPP2R1A'))
) g on g.sample_id = cs.sample_id;
Sample data text files
patients - https://drive.google.com/open?id=1NhRkHvvydmZ5ilHJ4TwKE_AslNFvCOcS
samples - https://drive.google.com/open?id=1Txdaa7JKOVMS3TZ8g9tkQUzZPkNc2m24
mutations - https://drive.google.com/open?id=1-HXEszbpcrkPX7MomJnkcAsVCKuzl-rJ
You seem to be over complicating this query when it should be a lot simpler. Here's an example on how to get the first 3 columns, you would just need to copy paste and replace for the rest.
SELECT s.patient_id,
s.sample_id,
MAX( CASE WHEN m.gene = 'BAP1' THEN 1 ELSE 0 END) AS BAP1,
MAX( CASE WHEN m.gene = 'PDGFRA' THEN 1 ELSE 0 END) AS PDGFRA,
MAX( CASE WHEN m.gene = 'KRAS' THEN 1 ELSE 0 END) AS KRAS
FROM samples s
LEFT JOIN mutations m ON s.sample_id = m.sample_id
GROUP BY s.patient_id,
s.sample_id;
If you want to create this query dynamically, you can do it to prevent writing a large amount of code.
DECLARE #Columns NVARCHAR(MAX),
#SQL NVARCHAR(MAX);
SELECT #Columns = ( SELECT CHAR(10) + CHAR(9) + ',MAX( CASE WHEN m.gene = ' + QUOTENAME( gene, '''') + ' THEN 1 ELSE 0 END) AS ' + QUOTENAME(gene)
FROM mutations
GROUP BY gene
FOR XML PATH(''), TYPE).value('./text()[1]', 'nvarchar(max)')
SET #SQL = N'SELECT s.patient_id ' + NCHAR(10)
+ N' ,s.sample_id '
+ #Columns + NCHAR(10)
+ N'FROM samples s ' + NCHAR(10)
+ N'LEFT JOIN mutations m ON s.sample_id = m.sample_id ' + NCHAR(10)
+ N'GROUP BY s.patient_id, ' + NCHAR(10)
+ N' s.sample_id;' + NCHAR(10)
PRINT sp_executesql --For debugging purposes
EXECUTE sp_executesql #SQL --, #ParametersDefinition, #Param1, #Param2, ..., #ParamN
I've got the following SQL to create a table:
declare #FirstColumnSPResultTable table
(
[HotelId] int,
[HotelName] nvarchar(256),
[2016 - Period 1] decimal(10,1),
[2016 - Period 2] decimal(10,1),
[2016 - Period 3] decimal(10,1),
[2016 - Period 4] decimal(10,1),
[Overall] decimal(10,1),
[#Jobs] int,
[Rank] int,
[OverallRow] bit
)
Where I have the [2016 - Period 1] to [2016 - Period 4] columns I would like to generate these based on a comma separated list of Period IDs that are passed into the Stored Procedure.
The PeriodIDs link to a Period table which contains ID and PeriodName.
I thought about creating the table with only the HotelId and HotelName then looping through the periods and creating each column using a WHILE loop and ALTER TABLE statement, somehow using it's name retrieved in a SELECT statement, then adding the last 4 columns to the table.
I think it is possible to do it this way but can anyone tell me a better way?
EDIT:
Full Solution using dynamic sql as suggested by #ADyson:
DECLARE #Sql nvarchar(max) = '
DECLARE #FirstColumnSPResultTable table ([HotelId] int,
[HotelName] nvarchar(256),'
DECLARE #FirstPeriodIdCommaDelimListAsColumns nvarchar(max)
SET #FirstPeriodIdCommaDelimListAsColumns = STUFF
(
(
SELECT ',' + QUOTENAME(p.[PeriodName]) + ' decimal(10,1) '
FROM [dbo].[Period] p WITH(NOLOCK)
WHERE p.PeriodId IN (SELECT Value FROM dbo.fn_Split(',', #FirstPeriodIdCommaDelimListInt))
ORDER BY p.[Year], p.[PeriodName]
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)'),1,1,''
) + ','
SET #Sql = #Sql + #FirstPeriodIdCommaDelimListAsColumns + '
[Overall] decimal(10,1),
[#Jobs] int,
[Rank] int,
[OverallRow] bit)'
so I create the first part of the table, then use FirstPeriodIdCommaDelimListAsColumns to store the next columns created from the periods as required. Then I finish off the table.
If you want to create a new table from the values in the other table, then you can use dynamic SQL to do this using the field names as variables, and build up a string to execute using the sp_executesql stored procedure.
What you're looking for is a pivot table. You can SELECT HotelId and HotelName (or whatever your key is) and PIVOT on PeriodID.
I have a SourceTable and a table variable #TQueries containing various T-SQL predicates that target SourceTable.
The expected result is to dynamically generate SELECT statements that return a list of Id's as specified by the predicates in #TQueries. Each dynamically generated SELECT statement also needs to execute in a particular order, and the final set of values needs to be unique and the ordering must be preserved.
Fortunately, there's a limit to how many values need to be retrieved and how many dynamic queries need to be generated. The Id list should contain at most 10 Ids, and we don't expect more than 7 queries.
The following is a sample of this setup, not the actual data/database:
-- Set up some test data, this is quick and dirty just to provide some data to test against
IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[SourceTable]') AND type in (N'U'))
BEGIN
-- Create a numbers table, sorta
SELECT TOP 20
IDENTITY(INT,1,1) AS Id,
ABS(CHECKSUM(NewId())) % 100 AS [SomeValue]
INTO [SourceTable]
FROM sysobjects a
END
DECLARE #TQueries TABLE (
[Ordinal] INT,
[WherePredicate] NVARCHAR(MAX),
[OrderByPredicate] NVARCHAR(MAX)
);
-- Simulate SELECTs with different order by that get different data due to varying WHERE clauses and ORDER conditions
INSERT INTO #TQueries VALUES ( 1, N'[Id] IN (6,11,13,7,10,3,15)', '[SomeValue] ASC' ) -- Sort Asc
INSERT INTO #TQueries VALUES ( 2, N'[Id] IN (9,15,14,20,17)', '[SomeValue] DESC' ) -- Sort Desc
INSERT INTO #TQueries VALUES ( 3, N'[Id] IN (20,10,1,16,11,19,9,15,17,6,2,3,13)', 'NEWID()' ) -- Sort Random
My main issue has been avoiding the use of a CURSOR or iterating through the rows one by one. The closest I've come to a set operation that meets this criteria is using a table variable to store the results of each query or a massive CTE.
Suggestions and comments are welcome.
Here's a solution that builds a single statement both to run all the queries and to return the results.
It uses a similar approach as in your answer when iterating over the #TQueries table, i.e. it also uses {...} tokens where column values from #TQuery should go, and it puts the values there with nested REPLACE() calls.
Other than that, it heavily depends on ranking functions, and I'm not sure if doesn't really abuse them. You'd need to test this method before deciding if it's better or worse than the one you've got so far.
DECLARE #QueryTemplate nvarchar(max), #FinalSQL nvarchar(max);
SET #QueryTemplate =
N'SELECT
[Id],
QueryRank = {Ordinal},
RowRank = ROW_NUMBER() OVER (ORDER BY {OrderByPredicate})
FROM [dbo].[SourceTable]
WHERE {WherePredicate}
';
SET #FinalSQL =
N'WITH AllData AS (
' +
SUBSTRING(
(
SELECT
'UNION ALL ' +
REPLACE(REPLACE(REPLACE(#QueryTemplate,
'{Ordinal}' , [Ordinal] ),
'{OrderByPredicate}', [OrderByPredicate]),
'{WherePredicate}' , [WherePredicate] )
FROM #TQueries
ORDER BY [Ordinal]
FOR XML PATH (''), TYPE
).value('.', 'nvarchar(max)'),
11, -- starting just after the first 'UNION ALL '
CAST(0x7FFFFFFF AS int) -- max int; no need to specify the exact length
) +
'),
RankedData AS (
SELECT
[Id],
QueryRank,
RowRank,
ValueRank = ROW_NUMBER() OVER (PARTITION BY [Id] ORDER BY QueryRank)
FROM AllData
)SELECT TOP (#top)
[Id]
FROM RankedData
WHERE ValueRank = 1
ORDER BY
QueryRank,
RowRank
';
PRINT #FinalSQL;
EXECUTE sp_executesql #FinalSQL, N'#top int', 10;
Basically, every subquery gets these auxiliary columns:
QueryRank – a constant value (within the subquery's result set) derived from [Ordinal];
RowRank – a ranking assigned to a row based on the [OrderByPredicate].
The result sets are UNIONed and then every entry of every unique value is again ranked (ValueRank) based on the query ranking.
When pulling the final result set, duplicates are suppressed (by the condition ValueRank = 1), and QueryRank and RowRank are used in the ORDER BY clause to preserve the original row order.
I used EXECUTE sp_executesql #query instead of EXECUTE (#query), because the former allows you to add parameters to the query. In particular, I parametrised the number of results to return (the argument of TOP). But you could certainly concatenate that value into the dynamic script directly, just like other things, if you prefer EXECUTE () over EXECUTE sq_executesql.
If you like, you can try this query at SQL Fiddle. (Note: the SQL Fiddle version replaces the #TQueries table variable with the TQueries table.)
This is what I've managed to piece together cobbled from my original response and improved upon by comments from #AndriyM
DECLARE #sql_prefix NVARCHAR(MAX);
SET #sql_prefix =
N'DECLARE #TResults TABLE (
[Ordinal] INT IDENTITY(1,1),
[ContentItemId] INT
);
DECLARE #max INT, #top INT;
SELECT #max = 10;';
DECLARE #sql_insert_template NVARCHAR(MAX), #sql_body NVARCHAR(MAX);
SET #sql_insert_template =
N'SELECT #top = #max - COUNT(*) FROM #TResults;
INSERT INTO #TResults
SELECT TOP (#top) [Id]
FROM [dbo].[SourceTable]
WHERE
{WherePredicate}
AND NOT EXISTS (
SELECT 1
FROM #TResults AS [tr]
WHERE [tr].[ContentItemId] = [SourceTable].[Id]
)
ORDER BY {OrderByPredicate};';
WITH Query ([Ordinal],[SqlCommand]) AS (
SELECT
[Ordinal],
REPLACE(REPLACE(#sql_insert_template, '{WherePredicate}', [WherePredicate]), '{OrderByPredicate}', [OrderByPredicate])
FROM #TQueries
)
SELECT
#sql_body = #sql_prefix + (
SELECT [SqlCommand]
FROM Query
ORDER BY [Ordinal] ASC
FOR XML PATH(''),TYPE).value('.', 'varchar(max)') + CHAR(13)+CHAR(10)
+N' SELECT * FROM #TResults ORDER BY [Ordinal]';
EXEC(#sql_body);
The basic idea is to use a table variable to hold the results of each query. I create a template for the SQL and replace the values in the template based on what is stored in #TQueries.
Once the entire script is completed I run it with EXEC.
I was looking at different ways of writing a stored procedure to return a "page" of data. This was for use with the ASP ObjectDataSource, but it could be considered a more general problem.
The requirement is to return a subset of the data based on the usual paging parameters; startPageIndex and maximumRows, but also a sortBy parameter to allow the data to be sorted. Also there are some parameters passed in to filter the data on various conditions.
One common way to do this seems to be something like this:
[Method 1]
;WITH stuff AS (
SELECT
CASE
WHEN #SortBy = 'Name' THEN ROW_NUMBER() OVER (ORDER BY Name)
WHEN #SortBy = 'Name DESC' THEN ROW_NUMBER() OVER (ORDER BY Name DESC)
WHEN #SortBy = ...
ELSE ROW_NUMBER() OVER (ORDER BY whatever)
END AS Row,
.,
.,
.,
FROM Table1
INNER JOIN Table2 ...
LEFT JOIN Table3 ...
WHERE ... (lots of things to check)
)
SELECT *
FROM stuff
WHERE (Row > #startRowIndex)
AND (Row <= #startRowIndex + #maximumRows OR #maximumRows <= 0)
ORDER BY Row
One problem with this is that it doesn't give the total count and generally we need another stored procedure for that. This second stored procedure has to replicate the parameter list and the complex WHERE clause. Not nice.
One solution is to append an extra column to the final select list, (SELECT COUNT(*) FROM stuff) AS TotalRows. This gives us the total but repeats it for every row in the result set, which is not ideal.
[Method 2]
An interesting alternative is given here (https://web.archive.org/web/20211020111700/https://www.4guysfromrolla.com/articles/032206-1.aspx) using dynamic SQL. He reckons that the performance is better because the CASE statement in the first solution drags things down. Fair enough, and this solution makes it easy to get the totalRows and slap it into an output parameter. But I hate coding dynamic SQL. All that 'bit of SQL ' + STR(#parm1) +' bit more SQL' gubbins.
[Method 3]
The only way I can find to get what I want, without repeating code which would have to be synchronized, and keeping things reasonably readable is to go back to the "old way" of using a table variable:
DECLARE #stuff TABLE (Row INT, ...)
INSERT INTO #stuff
SELECT
CASE
WHEN #SortBy = 'Name' THEN ROW_NUMBER() OVER (ORDER BY Name)
WHEN #SortBy = 'Name DESC' THEN ROW_NUMBER() OVER (ORDER BY Name DESC)
WHEN #SortBy = ...
ELSE ROW_NUMBER() OVER (ORDER BY whatever)
END AS Row,
.,
.,
.,
FROM Table1
INNER JOIN Table2 ...
LEFT JOIN Table3 ...
WHERE ... (lots of things to check)
SELECT *
FROM stuff
WHERE (Row > #startRowIndex)
AND (Row <= #startRowIndex + #maximumRows OR #maximumRows <= 0)
ORDER BY Row
(Or a similar method using an IDENTITY column on the table variable).
Here I can just add a SELECT COUNT on the table variable to get the totalRows and put it into an output parameter.
I did some tests and with a fairly simple version of the query (no sortBy and no filter), method 1 seems to come up on top (almost twice as quick as the other 2). Then I decided to test probably I needed the complexity and I needed the SQL to be in stored procedures. With this I get method 1 taking nearly twice as long as the other 2 methods. Which seems strange.
Is there any good reason why I shouldn't spurn CTEs and stick with method 3?
UPDATE - 15 March 2012
I tried adapting Method 1 to dump the page from the CTE into a temporary table so that I could extract the TotalRows and then select just the relevant columns for the resultset. This seemed to add significantly to the time (more than I expected). I should add that I'm running this on a laptop with SQL Server Express 2008 (all that I have available) but still the comparison should be valid.
I looked again at the dynamic SQL method. It turns out I wasn't really doing it properly (just concatenating strings together). I set it up as in the documentation for sp_executesql (with a parameter description string and parameter list) and it's much more readable. Also this method runs fastest in my environment. Why that should be still baffles me, but I guess the answer is hinted at in Hogan's comment.
I would most likely split the #SortBy argument into two, #SortColumn and #SortDirection, and use them like this:
…
ROW_NUMBER() OVER (
ORDER BY CASE #SortColumn
WHEN 'Name' THEN Name
WHEN 'OtherName' THEN OtherName
…
END *
CASE #SortDirection
WHEN 'DESC' THEN -1
ELSE 1
END
) AS Row
…
And this is how the TotalRows column could be defined (in the main select):
…
COUNT(*) OVER () AS TotalRows
…
I would definitely want to do a combination of a temp table and NTILE for this sort of approach.
The temp table will allow you to do your complicated series of conditions just once. Because you're only storing the pieces you care about, it also means that when you start doing selects against it further in the procedure, it should have a smaller overall memory usage than if you ran the condition multiple times.
I like NTILE() for this better than ROW_NUMBER() because it's doing the work you're trying to accomplish for you, rather than having additional where conditions to worry about.
The example below is one based off a similar query I'm using as part of a research query; I have an ID I can use that I know will be unique in the results. Using an ID that was an identity column would also be appropriate here, though.
--DECLARES here would be stored procedure parameters
declare #pagesize int, #sortby varchar(25), #page int = 1;
--Create temp with all relevant columns; ID here could be an identity PK to help with paging query below
create table #temp (id int not null primary key clustered, status varchar(50), lastname varchar(100), startdate datetime);
--Insert into #temp based off of your complex conditions, but with no attempt at paging
insert into #temp
(id, status, lastname, startdate)
select id, status, lastname, startdate
from Table1 ...etc.
where ...complicated conditions
SET #pagesize = 50;
SET #page = 5;--OR CAST(#startRowIndex/#pagesize as int)+1
SET #sortby = 'name';
--Only use the id and count to use NTILE
;with paging(id, pagenum, totalrows) as
(
select id,
NTILE((SELECT COUNT(*) cnt FROM #temp)/#pagesize) OVER(ORDER BY CASE WHEN #sortby = 'NAME' THEN lastname ELSE convert(varchar(10), startdate, 112) END),
cnt
FROM #temp
cross apply (SELECT COUNT(*) cnt FROM #temp) total
)
--Use the id to join back to main select
SELECT *
FROM paging
JOIN #temp ON paging.id = #temp.id
WHERE paging.pagenum = #page
--Don't need the drop in the procedure, included here for rerunnability
drop table #temp;
I generally prefer temp tables over table variables in this scenario, largely so that there are definite statistics on the result set you have. (Search for temp table vs table variable and you'll find plenty of examples as to why)
Dynamic SQL would be most useful for handling the sorting method. Using my example, you could do the main query in dynamic SQL and only pull the sort method you want to pull into the OVER().
The example above also does the total in each row of the return set, which as you mentioned was not ideal. You could, instead, have a #totalrows output variable in your procedure and pull it as well as the result set. That would save you the CROSS APPLY that I'm doing above in the paging CTE.
I would create one procedure to stage, sort, and paginate (using NTILE()) a staging table; and a second procedure to retrieve by page. This way you don't have to run the entire main query for each page.
This example queries AdventureWorks.HumanResources.Employee:
--------------------------------------------------------------------------
create procedure dbo.EmployeesByMartialStatus
#MaritalStatus nchar(1)
, #sort varchar(20)
as
-- Init staging table
if exists(
select 1 from sys.objects o
inner join sys.schemas s on s.schema_id=o.schema_id
and s.name='Staging'
and o.name='EmployeesByMartialStatus'
where type='U'
)
drop table Staging.EmployeesByMartialStatus;
-- Populate staging table with sort value
with s as (
select *
, sr=ROW_NUMBER()over(order by case #sort
when 'NationalIDNumber' then NationalIDNumber
when 'ManagerID' then ManagerID
-- plus any other sort conditions
else EmployeeID end)
from AdventureWorks.HumanResources.Employee
where MaritalStatus=#MaritalStatus
)
select *
into #temp
from s;
-- And now pages
declare #RowCount int; select #rowCount=COUNT(*) from #temp;
declare #PageCount int=ceiling(#rowCount/20); --assuming 20 lines/page
select *
, Page=NTILE(#PageCount)over(order by sr)
into Staging.EmployeesByMartialStatus
from #temp;
go
--------------------------------------------------------------------------
-- procedure to retrieve selected pages
create procedure EmployeesByMartialStatus_GetPage
#page int
as
declare #MaxPage int;
select #MaxPage=MAX(Page) from Staging.EmployeesByMartialStatus;
set #page=case when #page not between 1 and #MaxPage then 1 else #page end;
select EmployeeID,NationalIDNumber,ContactID,LoginID,ManagerID
, Title,BirthDate,MaritalStatus,Gender,HireDate,SalariedFlag,VacationHours,SickLeaveHours
, CurrentFlag,rowguid,ModifiedDate
from Staging.EmployeesByMartialStatus
where Page=#page
GO
--------------------------------------------------------------------------
-- Usage
-- Load staging
exec dbo.EmployeesByMartialStatus 'M','NationalIDNumber';
-- Get pages 1 through n
exec dbo.EmployeesByMartialStatus_GetPage 1;
exec dbo.EmployeesByMartialStatus_GetPage 2;
-- ...etc (this would actually be a foreach loop, but that detail is omitted for brevity)
GO
I use this method of using EXEC():
-- SP parameters:
-- #query: Your query as an input parameter
-- #maximumRows: As number of rows per page
-- #startPageIndex: As number of page to filter
-- #sortBy: As a field name or field names with supporting DESC keyword
DECLARE #query nvarchar(max) = 'SELECT * FROM sys.Objects',
#maximumRows int = 8,
#startPageIndex int = 3,
#sortBy as nvarchar(100) = 'name Desc'
SET #query = ';WITH CTE AS (' + #query + ')' +
'SELECT *, (dt.pagingRowNo - 1) / ' + CAST(#maximumRows as nvarchar(10)) + ' + 1 As pagingPageNo' +
', pagingCountRow / ' + CAST(#maximumRows as nvarchar(10)) + ' As pagingCountPage ' +
', (dt.pagingRowNo - 1) % ' + CAST(#maximumRows as nvarchar(10)) + ' + 1 As pagingRowInPage ' +
'FROM ( SELECT *, ROW_NUMBER() OVER (ORDER BY ' + #sortBy + ') As pagingRowNo, COUNT(*) OVER () AS pagingCountRow ' +
'FROM CTE) dt ' +
'WHERE (dt.pagingRowNo - 1) / ' + CAST(#maximumRows as nvarchar(10)) + ' + 1 = ' + CAST(#startPageIndex as nvarchar(10))
EXEC(#query)
At result-set after query result columns:
Note:
I add some extra columns that you can remove them:
pagingRowNo : The row number
pagingCountRow : The total number of rows
pagingPageNo : The current page number
pagingCountPage : The total number of pages
pagingRowInPage : The row number that started with 1 in this page