We have 2 tables with identical structure and based on a variable I want to choose which table to select on with out having to write 2 queries in my procedure.
Is this possible?
I tried
declare #table int
set #table = 1
Select orderID, Quantity
from case when #table = 1 then tblOrders else tblSubscriptionOrders end
where filled = 0
But that did not work
You would need to use dynamic SQL for this (assuming you want to scale it to more than just 2 tables), which would work but is suboptimal as SQL will not generate statistics for it and have a harder time optimizing the query.
declare #table sysname
declare #SQL varchar(1000)
set #table = 'MyTable'
SET #SQL='SELECT orderID, Quantity FROM ' + QUOTENAME(#table) + ' WHERE filled=0'
exec sp_executesql #SQL
or, in a stored procedure:
CREATE PROCEDURE p_ConditionalSelect #table sysname
as
declare #SQL varchar(1000)
set #table = 'MyTable'
SET #SQL='SELECT orderID, Quantity FROM ' + QUOTENAME(#table) + ' WHERE filled=0'
exec sp_executesql #SQL
If it's just two tables you could do:
Declare #table = 1
SELECT *
FROM Table1
WHERE <stuff>
AND #Table = 1
UNION ALL
SELECT *
FROM Table2
WHERE <stuff>
AND #Table = 2
The filter on #table will result in only one of the two halves showing data.
One option is to use Dynamic SQL but if performance isn't an immediate issue, much simpler is to just UNION the tables and add a dummy [table] column to select from.
SELECT orderID, Quantity
FROM (
SELECT [table] = 1, orderID, Quantity
FROM tblOrders
UNION ALL
SELECT [table] = 2, orderID, Quantity
FROM tblSubscriptionOrders
) t
WHERE t.Table = #table
Related
I'm pretty new to sql so any help will be much appreciated
I have a table containing a list of table names in a column of a table and I need to retrieve a column called [Last Refreshed] from all the tables listed. The tables all have different structures but they all have the [Last Refreshed] Column. I have managed to insert the tablenames into a sql variable but up to this point I am kind of stuck.
I hope I managed to explain what I need but I have attached my code as well.
Declare #tables nvarchar(max)
Declare #sql nvarchar(max)
Declare #cnt int
DECLARE #Counter int
SET #Counter = 1
DECLARE #RowCount INT
SET #RowCount = (SELECT COUNT(*)
FROM (
SELECT * FROM TABLE_LIST1
UNION
SELECT * FROM TABLE_LIST2) data )
DROP TABLE #DB_DUMMY
CREATE TABLE #DB_DUMMY (
[TABLENAME] VARCHAR(512),
[LAST_REFRESHED] VARCHAR(533)
);
WHILE ( #Counter <= #RowCount)
BEGIN
SELECT #tables = FinalTable, #cnt = Row_num from (
SELECT FinalTable , ROW_NUMBER() OVER(ORDER BY FinalTable DESC) AS Row_num
FROM (
SELECT FinalTable FROM TABLE_LIST1
UNION
SELECT FinalTable FROM ABLE_LIST2) data
group by FinalTable) a
where Row_num = #Counter
--This part doesnt work
INSERT INTO #DB_DUMMY(TABLENAME,LAST_REFRESHED)
SELECT #tables , [Last Refreshed] from #tables
SET #Counter = #Counter + 1
END
exec(#sql)
I expect to see a list of tablenames as well as the last refresh in the temporary table #DB_DUMMY
i add the [Last Refreshed] column to my tables and write this query and give me the correct answer
DROP TABLE IF EXISTS #DB_DUMMY
CREATE TABLE #DB_DUMMY (
[TABLENAME] VARCHAR(512),
[LAST_REFRESHED] VARCHAR(533)
);
DECLARE #COMMAND NVARCHAR(MAX)
SELECT #COMMAND = STRING_AGG(' INSERT INTO #DB_DUMMY SELECT DISTINCT '+CHAR(39)+T.name+CHAR(39)+',['+C.name+'] FROM '+S.name+'.'+T.name + ' GO', CHAR(13)+CHAR(10))
FROM sys.all_columns C
INNER JOIN sys.tables T ON C.object_id = T.object_id
INNER JOIN sys.schemas S ON T.schema_id = S.schema_id
WHERE C.name = 'Last Refreshed'
PRINT(#COMMAND)
EXEC(#COMMAND)
SELECT * FROM #DB_DUMMY
two first line with IF EXISTS is new syntax in sql server 2017
Just a suggestion You could use a INSERT SELECT
INSERT INTO #DB_DUMMY(TABLENAME,LAST_REFRESHED)
SELECT 'TABLE_LIST1', LAST_REFRESHED
FROM TABLE_LIST1
UNION ALL
SELECT 'TABLE_LIST2', LAST_REFRESHED
FROM TABLE_LIST2
UNION ALL
.....
SELECT 'TABLE_LISTN', LAST_REFRESHED
FROM TABLE_LISTN
Try something like this:
declare cur cursor for Select TableName From TABLE_LIST
declare #tablename nvarchar(max)
declare #sqlstring nvarchar(max)
open cur
fetch next from cur into #tablename
while ##fetch_status=0
begin
set #sqlstring = 'SELECT ''' + #tablename + ''' AS ''TABLE'', [LAST_REFRESHED] FROM ' + #tablename
exec sp_executesql #sqlstring
fetch next from cur into #tablename
end
close cur
deallocate cur
;
It is the weekend and I don't have access to a database to test on, so it may need some adjusting. Here is a fiddle with the sample code, but it only returns the first table http://sqlfiddle.com/#!18/a5b55b/2 (I think the fiddle execution mechanism interferes with the cursor.)
This answer is based upon the code here: I have the same column in multiple tables, and want to update that column in all tables to a specific value. How can I do this?
Note that there is no need to maintain a list of tables with the column. You can generate it dynamically from INFORMATION_SCHEMA.COLUMNS
Another possible approach is to generate and execute a dynamic statement (it's not possible to use a variable for the name of a column or a table):
Table:
CREATE TABLE #TableNames (
[TableName] nvarchar(128)
)
INSERT INTO #TableNames
([TableName])
VALUES
(N'Table1'),
(N'Table2'),
(N'Table3'),
(N'Table4'),
(N'Table5')
Statement:
-- Generate statement
DECLARE #stm nvarchar(max) = N''
SELECT #stm = CONCAT(
#stm,
N'INSERT INTO #DB_DUMMY (TABLENAME, LAST_REFRESHED) ',
N'SELECT ''',
[TableName],
N''' AS [TableName], [LastRefreshed] FROM ',
QUOTENAME([TableName]),
N'; '
)
FROM #TableNames
-- Execute statement
PRINT #stm
EXEC sp_executesql #stm
Simplified example of what I have:
Two tables (table_1 and table_2) which have one similar column (Id) but also several "payload" columns with different names (col_1_1, col_2_1, col_2_2). Amount of "payload" columns is different for different tables.
I am interested in extracting the IDs from both tables into another table for rows which have all "payload" columns empty.
There is a list of all "payload" columns for all tables which can be used (#temp)
This is how it is done with cursor:
CREATE TABLE #temp (tab nvarchar(20) not null, col nvarchar(20) not null)
INSERT INTO #temp SELECT 'table_1','col_1_1' UNION SELECT 'table_2','col_2_1' UNION SELECT 'table_2','col_2_2'
DECLARE #table_name nvarchar(20)
DECLARE #sql nvarchar(max)
DECLARE curs CURSOR FOR (SELECT DISTINCT tab FROM #temp)
OPEN curs
FETCH NEXT FROM curs INTO #table_name
WHILE ##FETCH_STATUS = 0
BEGIN
SELECT #sql = ISNULL(#sql,'')+col+' IS NULL AND ' FROM #temp WHERE tab = #table_name
SET #sql += 'Id IS NOT NULL'
SET #sql = 'INSERT INTO #temp_master SELECT ID FROM '+#table_name+' WHERE '+#sql
print #sql
SET #sql = ''
FETCH NEXT FROM curs INTO #table_name
END
CLOSE curs
DEALLOCATE curs
This is the result:
INSERT INTO #temp_master SELECT ID FROM table_1 WHERE col_1_1 IS NULL AND Id IS NOT NULL
INSERT INTO #temp_master SELECT ID FROM table_2 WHERE col_2_1 IS NULL AND col_2_2 IS NULL AND Id IS NOT NULL
Is it possible to remove the cursor to get the same resulting dynamic query? The problem is that I am unable to have dynamic "IS NULL AND" part for different tables when I remove the cursor.
It's possible to get rid of that cursor. This is probably what you need:
CREATE TABLE #temp (tab nvarchar(20) not null, col nvarchar(20) not null)
INSERT INTO #temp SELECT 'table_1','col_1_1' UNION SELECT 'table_2','col_2_1' UNION SELECT 'table_2','col_2_2'
DECLARE #table_name nvarchar(20)
DECLARE #sql nvarchar(max) = ''
select #sql = 'INSERT INTO #temp_master SELECT ID FROM ' + t.tab + ' WHERE Id IS NOT NULL AND ' + substring(t.cols, 0, len(t.cols)-3) + '
' + #sql from
(
SELECT
distinct
t2.tab,
stuff(
(
select t1.col + cast(' IS NULL AND ' as varchar(max))
from #temp t1
WHERE t1.tab = t2.tab
order by t1.tab
for xml path('')
), 1, 0, '') AS cols
FROM
#temp t2
) as t
order by t.tab desc
print #sql
drop table #temp
That is a regular CONCAT question, you can find many approaches to accomplish it without cursor. One of approaches is a cursor by the way and it's not that bad for such a task.
Another and more popular - FOR XML which can guarantee row order if any defined:
DECLARE #sql VARCHAR(MAX)
CREATE TABLE #temp (tab nvarchar(20) not null, col nvarchar(20) not null)
INSERT INTO #temp SELECT 'table_1','col_1_1' UNION SELECT 'table_2','col_2_1' UNION SELECT 'table_2','col_2_2'
SET #sql = (SELECT (
SELECT '
INSERT INTO #temp_master (ID) SELECT t.ID FROM '+t.tab +' t WHERE t.Id IS NOT NULL'
+ (select ' AND t.' + tt.col + ' is NULL' from #temp tt WHERE tt.tab = t.tab FOR XML PATH(''), TYPE).value('.', 'varchar(max)')
FROM #temp t
GROUP BY t.tab
FOR XML PATH(''), TYPE).value('.', 'varchar(max)'))
PRINT #sql
DROP TABLE #temp
A little "tricky" thing is that you have two things to collaps:
many queries (separate for specific table)
many columns per table
So you there is one inner FOR XML to collapse columns per table and another - to combine all queries into one big script.
I need to run multiple select count queries to count how many people are available at certain times through the day to plot into a table from ms sql server.
I have the below sql which works, but is returning each count as a new table, I would like them to all in one table on different columns.
DECLARE #Day varchar(max)
SET #Day = 'Sunday'
DECLARE #Provider varchar(max)
SET #Provider = '58611'
DECLARE #sqlText varchar(max);
SET #sqlText = N'SELECT COUNT(*) AS Available0700
FROM tblCarersRota INNER JOIN tblCarersProviders ON tblCarersProviders.CarerID = tblCarersRota.CarerID
WHERE Rotation = 2 AND tblCarersProviders.ProviderID = '''+ #Provider + ''' AND ''07:00'' between ' + #Day + 'StartTime AND ' + #Day + 'EndTime '
Exec (#sqlText)
SET #sqlText = N'SELECT COUNT(*) AS Available0800
FROM tblCarersRota INNER JOIN tblCarersProviders ON tblCarersProviders.CarerID = tblCarersRota.CarerID
WHERE Rotation = 2 AND tblCarersProviders.ProviderID = '''+ #Provider + ''' AND ''08:00'' between ' + #Day + 'StartTime AND ' + #Day + 'EndTime '
Exec (#sqlText)
Actual current result:
Available0700
21
Available0800
22
Desired result:
Available0700 || Available0800
21 || 22
I have looked at where you select (select query 1) (select query 2) but I can't get that to work with the dynamic sqltext.
How can I modify my selects to get them to all return as 1 table?
Thanks
Option 1, put it in 2 rows with UNION ALL:
SELECT COUNT(*) as Counts, 'Available0700' AvailableTime
FROM ...
UNION all
SELECT COUNT(*) as Counts, 'Available0800' AvailableTime
FROM ...
Option 2, in 2 columns with subqueries:
SELECT (SELECT COUNT(*) FROM ...) as Available0700,
(SELECT COUNT(*) FROM ...) as Available0800
I think you can store these values in variables and finally select these variables in your select query.
Below is an example code in which i have used a table variable to execute the dynamic queries and store the records and finally used a PIVOT query to fetch the require output.
DECLARE #tablevar TABLE
(
Query VARCHAR(100),
Cnt INT
)
DECLARE #sqlText varchar(max)
SET #sqlText = N'SELECT ''Available Value 1'', 100 '
INSERT INTO #tablevar
Exec (#sqlText)
SET #sqlText = N'SELECT ''Available Value 2'', 200 '
INSERT INTO #tablevar
Exec (#sqlText)
SET #sqlText = N'SELECT ''Available Value 3'', 300 '
INSERT INTO #tablevar
Exec (#sqlText)
SELECT * FROM #tablevar
PIVOT(SUM(Cnt) FOR Query IN([Available Value 1], [Available Value 2], [Available Value 3])) AS PIV
Above code is an example, please replace it with your actual code accordingly.
Thanks
Why did you use dynamic query? You can use case when inside operator COUNT in such way: COUNT(CASE WHEN <yours filter with time 7.00 > then 1 else null end) AS Available0700 , COUNT(CASE WHEN <yours filter with time 8.00 > then 1 else null end) AS Available0800.
I have two tables, Values and SpecialValues.
Values has two columns, RecordID and ValueName.
SpecialValues is a table which contains a single row, and thirty columns named SpecialValueName1, SpecialValueName2, SpecialValueName3, etc.
There are obvious database design problems with this system.
That aside, can someone explain to me how to query SpecialValues so that I can get a collection of all the values of every row from the table, and exclude them from a Select from Values?
There's probably some easy way to do this or create a View for it or something, but I think looking at this code might have broken me for the moment...
EDIT: I'd like a query to get all the individual values from every row and column of a given table (in this case the SpecialValues table) so that the query does not need to be updated the next time someone adds another column to the SpecialValues table.
This creates a #SpecialValuesColumns temporary table to store all the column names from SpecialValues.
It then uses a cursor to insert all the values from each of those columns into another temporary table #ProtectedValues.
It then uses a NOT IN query to exclude all of those values from a query to Values.
This code is bad and I feel bad for writing it, but it seems like the least-worst option open to me right now.
DECLARE #SpecialColumnsCount INT;
DECLARE #Counter INT;
DECLARE #CurrentColumnName VARCHAR(255);
DECLARE #ExecSQL VARCHAR(1024);
SET #Counter = 1;
CREATE TABLE #ProtectedValues(RecordID INT IDENTITY(1,1) PRIMARY KEY NOT NULL, Value VARCHAR(255));
DECLARE #SpecialValuesColumns TABLE (RecordID INT IDENTITY(1,1) PRIMARY KEY NOT NULL, ColumnName VARCHAR(255));
INSERT INTO #SpecialValuesColumns (ColumnName)
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE
TABLE_NAME = 'SpecialValues' AND
DATA_TYPE = 'varchar' AND
CHARACTER_MAXIMUM_LENGTH = 255
SELECT #SpecialColumnsCount = COUNT(*) FROM #SpecialValuesColumns
WHILE #Counter <= #SpecialColumnsCount
BEGIN
SELECT #CurrentColumnName = ColumnName FROM #SpecialValuesColumns WHERE RecordID = #Counter;
SET #ExecSQL = 'INSERT INTO #ProtectedValues (Value) SELECT ' + #CurrentColumnName + ' FROM SpecialValues'
EXEC (#ExecSQL)
SET #Counter = #Counter + 1;
END
SELECT * FROM Values WHERE ValueName NOT IN (SELECT ValueName COLLATE DATABASE_DEFAULT FROM #ProtectedValues)
DROP TABLE #ProtectedValues;
I might have misunderstood but doesn't this do it?
SELECT * FROM Values
WHERE ValueName NOT IN (
SELECT SpecialValueName1 FROM SpecialValues
UNION SELECT SpecialValueName2 FROM SpecialValues
UNION SELECT SpecialValueName3 FROM SpecialValues
etc..
)
You could of course make the subquery into a view instead.
*Edit:
This is quite ugly but should solve your problem:
First Create procedure #1
CREATE PROCEDURE [dbo].[SP1]
As
DECLARE
#Query nvarchar(MAX),
#Table nvarchar(255),
#Columns nvarchar(255)
CREATE TABLE #TempTable (Value nvarchar(255))
SET #Table = 'SpecialValues'
SELECT [COLUMN_NAME]
FROM [INFORMATION_SCHEMA].[COLUMNS]
WHERE [TABLE_NAME] = #Table
DECLARE Table_Cursor CURSOR FOR
SELECT COLUMN_NAME
FROM [INFORMATION_SCHEMA].[COLUMNS]
WHERE [TABLE_NAME] = #Table
OPEN Table_Cursor
FETCH NEXT FROM Table_Cursor INTO #Columns
WHILE ##FETCH_STATUS = 0
BEGIN
INSERT INTO #TempTable EXEC SP2 #Columns = #Columns, #Table = #Table
FETCH NEXT FROM Table_Cursor INTO #Columns
END
CLOSE Table_Cursor
DEALLOCATE Table_Cursor
SELECT ValueName FROM Value WHERE Value NOT IN (SELECT * FROM #TempTable)
TRUNCATE TABLE #TempTable
DROP TABLE #TempTable
Then Create procedure #2
CREATE PROCEDURE [dbo].[SP2]
#Columns nvarchar(255) = '',
#Table nvarchar(255)
AS
DECLARE
#Query nvarchar(MAX)
SET #Query = 'SELECT TOP 1 CONVERT(nvarchar, ' + #Columns + ') FROM ' + #Table
EXEC (#Query)
Then lastly execute the procedure
EXEC SP1
You need to unpivot the values in specialvalues. A pretty easy way to do that is with cross apply syntax:
select sv.value
from specialvalues sv cross apply
(values(sv.SpecialValueName1), (sv.SpecialValueName2), . . .
) sv(value)
where sv.value is not null;
You can exclude these from the list using not in, not exists or a left join.
What ever way you cut it, you have to specify the columns in SpecialValues, you can do this with a long set of UNION queries, or use UNPIVOT:
select SpecialValue
from (select SpecialValueName1,SpecialValueName2,SpecialValueName3 from #SpecialValues) p
unpivot (SpecialValue FOR ROW IN (SpecialValueName1,SpecialValueName2,SpecialValueName3))
AS unpvt
You can then incorporate this into a query on Values using NOT IN
select * from [Values] where ValueName not in (
select SpecialValue
from (select SpecialValueName1,SpecialValueName2,SpecialValueName3 from #SpecialValues) p
unpivot (SpecialValue FOR ROW IN (SpecialValueName1,SpecialValueName2,SpecialValueName3))
AS unpvt
)
My query returns 26 table names.
select name from sys.tables where name like '%JPro_VP_Service%'
Now I'm trying to write a query to check in every table return from the above query.
--consider this is my first table
select * from JPro_VP_Service
where row_id like '%1-101%' or row_id like '%1-102%'
-- likewise I want to search in 26 tables return from above query
I think I need to write for or cursor to accomplish this.
Can anyone help me how to achieve this?
The easiest way to do this is
Try this:
SELECT 'select * from ' + name
+ ' where row_id like ''%1-101%'' or row_id like ''%1-102%'''
FROM sys.tables
WHERE name LIKE '%JPro_VP_Service%'
you will get all tables together with the same conditions. You could execute them together.
Yes, you would have to use a cursor for this, and probably also dynamic sql
Also see
Generate dynamic SQL statements in SQL Server
Dynamic SQL PROs & CONs
DECLARE #mn INT
DECLARE #mx INT
DECLARE #tblname VARCHAR(100);
WITH cte
AS (SELECT Row_number()
OVER (
ORDER BY (SELECT 0)) AS rn,
name
FROM sys.tables
WHERE name LIKE '%JPro_VP_Service%')
SELECT #mn = Min(rn),
#mx = Max(rn)
FROM cte
WHILE( #mn >= #mx )
BEGIN
SELECT #tblname = name
FROM cte
WHERE rn = #mn
SELECT *
FROM #tblname
WHERE row_id LIKE '%1-101%'
OR row_id LIKE '%1-102%'
--Do something else
SET #mn=#mn + 1
END
This route may work, though you might want the results saved to a table:
DECLARE #tables TABLE(
ID INT IDENTITY(1,1),
Name VARCHAR(100)
)
INSERT INTO #tables (Name)
SELECT name
FROM sys.tables
WHERE name like '%JPro_VP_Service%'
DECLARE #b INT = 1, #m INT, #table VARCHAR(100), #cmd NVARCHAR(MAX)
SELECT #m = MAX(ID) FROM #tables
WHILE #b <= #m
BEGIN
SELECT #table = Name FROM #tables WHERE ID = #b
SET #cmd = 'select * from ' + #table + '
where row_id like ''%1-101%'' or row_id like ''%1-102%''
'
EXECUTE sp_executesql #cmd
SET #b = #b + 1
SET #cmd = ''
END