I want to set local variables or pass parameters from Excel to SQL. I've found similar questions, but all referred to old versions of Excel and/or the answers showed how to filter or manipulate output from a generic SQL query in the Power Query Editor, rather than pass a parameter or modify the SQL, so that the SQL Server supplies data in the needed form.
I'm building a large Microsoft Excel spreadsheet that depends on ten different SQL queries, all against a common SQL Server database. Excel and SQL Server are installed on my laptop and are current versions (as of 16 Mar 2022). All ten queries share a common date restriction, imposed in the WHERE clauses of the queries. The tables accessed and the form of output are very different, so there is no easy way to combine the ten queries into a single query. The queries contain multiple levels of aggregation (e.g. SUM(...)) so I need to restrict the records accessed prior to aggregation and passing results from the query back to Excel.
As currently written, each query begins by setting two date values in local variables. For example,
DECLARE #BEGIN_DATE AS smalldatetime;
DECLARE #END_DATE AS smalldatetime;
#BEGIN_DATE = CAST('2021-03-01 00:00' AS smalldatetime);
#END_DATE = CAST('2021-03-02 23:59' AS smalldatetime);
Every one of the ten queries includes a line in the WHERE clause similar to
WHERE
PickUpDate BETWEEN #BEGIN_DATE AND #END_DATE
Every query will use the same pair of dates. However, the column filtered (PickUpDate above) changes from one query to the next.
As it is, I have to manually edit each of the ten queries to change the two dates--twenty edits in all. This is time-consuming and error-prone. Ideally, I'd like to set the date range in the spreadsheet, in a pop-up dialog box, or any other convenient way and pass the dates to the SQL queries. Then by selecting Data > Refresh All in Excel, update all my tables at once.
Is this possible, and if so, how does one do it?
The answer from David Browne is generally on-target. But I found some difficulties reading data from an Excel table directly into the SQL, given security restrictions in the latest version of Excel/Power Query. Also, since this was the first time I worked directly in M-code and the advanced editor, it was challenging to fill-in the gaps.
I finally got a nice solution running; here is what worked for me.
First, I stored the parameter values in a two-column table. My table is named "ParameterTable" with column headers named "Parameter_Name" and "Value". The value(s) to pass to SQL Server are stored in the Value column. My table has two rows with row entries labeled "Begin_DateTime" and "End_DateTime".
Secondly I created a callable function named “ftnGetParameter.” Select Data > Get Data > From Other Sources > Blank Query. Then select “Advanced Editor.” Delete any boilerplate added by Excel, and enter and save this function
let theParameter=(TableName,ParameterLabel) =>
let
Source=Excel.CurrentWorkbook(){[Name=TableName]}[Content],
value = Source{[Parameter_Name=ParameterLabel]}[Value]
in
value
in
theParameter
Thirdly, code-up your SQL statement as usual. I was trying to pass dates to SQL, so I initially coded with string literals. Enter the query in the usual way. I used Data > Get Data > From Database > From SQL Server Database. Then pasted in the SQL. The two relevant lines in my query looked like this:
DECLARE #BEGIN_DATE AS SMALLDATETIME='2021-01-01 00:00';
DECLARE #END_DATE AS SMALLDATETIME='2021-12-31 23:59';
You could skip this step, but it allowed me to get complex SQL code entered, formatted, and running before I invoked the function to pass the parameters.
Finally, simply replace the string literals in the SQL with code to call the function. My first few lines of M-code looks like this:
let
Source = Sql.Database("DESKTOP-04P8E8C", "nfbdata",
[Query=
"
DECLARE #BEGIN_DATE AS SMALLDATETIME= '" & ftnGetParameter("ParameterTable","Begin_DateTime") & "';
DECLARE #END_DATE AS SMALLDATETIME='" & ftnGetParameter("ParameterTable","End_DateTime") & "' (… the query continues )
Excel will issue some warnings about running the query and prompt you to edit permissions. Once permission has been granted, the function reads the text from the parameter table and passes it into the SQL.
I found that the function call was not optional. Apparently, importing the code directly into a native call to SQL Server is considered an unacceptable security risk.
Many thanks to Mr. David Browne. His post definitely points in the right direction.
You can reference a table on a sheet from Power Query and integrate values from that table into your other queries. Eg if ParameterTable is a single-row table on some worksheet with a column called "StartDate", something like
let
theDate = Date.From( Record.Field(Table.First(ParameterTable),"StartDate") ),
Source = Sql.Databases("localhost"),
AdventureWorksDW2017 = Source{[Name="AdventureWorksDW2017"]}[Data],
dbo_DimDate = AdventureWorksDW2017{[Schema="dbo",Item="DimDate"]}[Data],
#"Filtered Rows" = Table.SelectRows(dbo_DimDate, each [FullDateAlternateKey] = theDate )
in
#"Filtered Rows"
for M query folding, or
let
theDate = Date.From( Record.Field(Table.First(ParameterTable),"StartDate") ),
sql = "
select *
from dimDate
where FullDateAlternateKey = '" & Text.From(theDate) & "'
",
Source = Sql.Database("localhost", "adventureworksdw2017", [Query=sql])
in
Source
for dynamic SQL.
I'm trying to figure out the best way to go about building a dynamic query and use it as a record source for a MS Access subform. I've got my WHERE clause statically assigned at the moment just so I could get the form built and make sure data was pulling properly. The main form will have 2 text boxes formatted as ShortDate and 2 subforms below with the query results. The first subform is the query grouped by Employee name and the second subform is a sum of department totals.
FWIW this is an Access 2010 ADP/ADE front end, SQL Server 2008 back end. My current SQL for the Dept totals is as follows:
SELECT COUNT(*) AS TotalNumEstimates, SUM(NumPanels) AS TotalNumPanels, SUM(PriceBase) AS TotalBasePrice, SUM(PriceBase) / SUM(NumPanels) AS ValuePricePerPanel
FROM dbo.tblBid
WHERE (Date > CONVERT(DATETIME, '2016-01-01 00:00:00', 102))
HAVING (SUM(NumPanels) > 0)
I plan on changing the WHERE clause to "WHERE Date BETWEEN #FromDate and #ToDate". Then on the Access form when the dates are set and a "Run Report" button is clicked, programatically set the OnClick event to pass the txtFromDate and txtToDate to the #FromDate and #ToDate respectively, but I can't quite figure that part out.
The only other option I can see would be to type out the whole SQL statement as a string with the txtFromDate and txtToDate declared in the OnClick event and change the subform record source to the new string. Is there a better way to go about doing this?
I believe I have figured out my initial problem of passing the textbox to the WHERE clause by creating a stored procedure. I will repost if I can't get the stored procedure to work, but it seems easy enough.
Use a [permanent] temporary table, which you then remove when the form unloads. If multiple users will use the form simultaneously, you'll need to add a session number of some sort to the name. So:
SELECT COUNT(*) AS TotalNumEstimates, SUM(NumPanels) AS TotalNumPanels, SUM(PriceBase) AS TotalBasePrice, SUM(PriceBase) / SUM(NumPanels) AS ValuePricePerPanel
INTO dbo.TempSubFormTable
FROM dbo.tblBid
WHERE Date > '2016-01-01'
HAVING SUM(NumPanels) > 0
Remove the recordsource from your subform, and give it a public interface:
Public Sub SetRecordSource(tbl as string)
Me.RecordSource = "SELECT * FROM tbl" 'ORDER BY ...
End Sub
Then, before the temporary table is created, make your subform invisible. After creating the temporary table,
Me.subformName.Visible = True
Me.subformName.SetRecordSource temporary_table_name 'without the dbo. part of the name
Locked. This question and its answers are locked because the question is off-topic but has historical significance. It is not currently accepting new answers or interactions.
What are some hidden features of SQL Server?
For example, undocumented system stored procedures, tricks to do things which are very useful but not documented enough?
Answers
Thanks to everybody for all the great answers!
Stored Procedures
sp_msforeachtable: Runs a command with '?' replaced with each table name (v6.5 and up)
sp_msforeachdb: Runs a command with '?' replaced with each database name (v7 and up)
sp_who2: just like sp_who, but with a lot more info for troubleshooting blocks (v7 and up)
sp_helptext: If you want the code of a stored procedure, view & UDF
sp_tables: return a list of all tables and views of database in scope.
sp_stored_procedures: return a list of all stored procedures
xp_sscanf: Reads data from the string into the argument locations specified by each format argument.
xp_fixeddrives:: Find the fixed drive with largest free space
sp_help: If you want to know the table structure, indexes and constraints of a table. Also views and UDFs. Shortcut is Alt+F1
Snippets
Returning rows in random order
All database User Objects by Last Modified Date
Return Date Only
Find records which date falls somewhere inside the current week.
Find records which date occurred last week.
Returns the date for the beginning of the current week.
Returns the date for the beginning of last week.
See the text of a procedure that has been deployed to a server
Drop all connections to the database
Table Checksum
Row Checksum
Drop all the procedures in a database
Re-map the login Ids correctly after restore
Call Stored Procedures from an INSERT statement
Find Procedures By Keyword
Drop all the procedures in a database
Query the transaction log for a database programmatically.
Functions
HashBytes()
EncryptByKey
PIVOT command
Misc
Connection String extras
TableDiff.exe
Triggers for Logon Events (New in Service Pack 2)
Boosting performance with persisted-computed-columns (pcc).
DEFAULT_SCHEMA setting in sys.database_principles
Forced Parameterization
Vardecimal Storage Format
Figuring out the most popular queries in seconds
Scalable Shared Databases
Table/Stored Procedure Filter feature in SQL Management Studio
Trace flags
Number after a GO repeats the batch
Security using schemas
Encryption using built in encryption functions, views and base tables with triggers
In Management Studio, you can put a number after a GO end-of-batch marker to cause the batch to be repeated that number of times:
PRINT 'X'
GO 10
Will print 'X' 10 times. This can save you from tedious copy/pasting when doing repetitive stuff.
A lot of SQL Server developers still don't seem to know about the OUTPUT clause (SQL Server 2005 and newer) on the DELETE, INSERT and UPDATE statement.
It can be extremely useful to know which rows have been INSERTed, UPDATEd, or DELETEd, and the OUTPUT clause allows to do this very easily - it allows access to the "virtual" tables called inserted and deleted (like in triggers):
DELETE FROM (table)
OUTPUT deleted.ID, deleted.Description
WHERE (condition)
If you're inserting values into a table which has an INT IDENTITY primary key field, with the OUTPUT clause, you can get the inserted new ID right away:
INSERT INTO MyTable(Field1, Field2)
OUTPUT inserted.ID
VALUES (Value1, Value2)
And if you're updating, it can be extremely useful to know what changed - in this case, inserted represents the new values (after the UPDATE), while deleted refers to the old values before the UPDATE:
UPDATE (table)
SET field1 = value1, field2 = value2
OUTPUT inserted.ID, deleted.field1, inserted.field1
WHERE (condition)
If a lot of info will be returned, the output of OUTPUT can also be redirected to a temporary table or a table variable (OUTPUT INTO #myInfoTable).
Extremely useful - and very little known!
Marc
sp_msforeachtable: Runs a command with '?' replaced with each table name.
e.g.
exec sp_msforeachtable "dbcc dbreindex('?')"
You can issue up to 3 commands for each table
exec sp_msforeachtable
#Command1 = 'print ''reindexing table ?''',
#Command2 = 'dbcc dbreindex(''?'')',
#Command3 = 'select count (*) [?] from ?'
Also, sp_MSforeachdb
Connection String extras:
MultipleActiveResultSets=true;
This makes ADO.Net 2.0 and above read multiple, forward-only, read-only results sets on a single database connection, which can improve performance if you're doing a lot of reading. You can turn it on even if you're doing a mix of query types.
Application Name=MyProgramName
Now when you want to see a list of active connections by querying the sysprocesses table, your program's name will appear in the program_name column instead of ".Net SqlClient Data Provider"
TableDiff.exe
Table Difference tool allows you to discover and reconcile differences between a source and destination table or a view. Tablediff Utility can report differences on schema and data. The most popular feature of tablediff is the fact that it can generate a script that you can run on the destination that will reconcile differences between the tables.
Link
A less known TSQL technique for returning rows in random order:
-- Return rows in a random order
SELECT
SomeColumn
FROM
SomeTable
ORDER BY
CHECKSUM(NEWID())
In Management Studio, you can quickly get a comma-delimited list of columns for a table by :
In the Object Explorer, expand the nodes under a given table (so you will see folders for Columns, Keys, Constraints, Triggers etc.)
Point to the Columns folder and drag into a query.
This is handy when you don't want to use heinous format returned by right-clicking on the table and choosing Script Table As..., then Insert To... This trick does work with the other folders in that it will give you a comma-delimited list of names contained within the folder.
Row Constructors
You can insert multiple rows of data with a single insert statement.
INSERT INTO Colors (id, Color)
VALUES (1, 'Red'),
(2, 'Blue'),
(3, 'Green'),
(4, 'Yellow')
If you want to know the table structure, indexes and constraints:
sp_help 'TableName'
HashBytes() to return the MD2, MD4, MD5, SHA, or SHA1 hash of its input.
Figuring out the most popular queries
With sys.dm_exec_query_stats, you can figure out many combinations of query analyses by a single query.
Link
with the commnad
select * from sys.dm_exec_query_stats
order by execution_count desc
The spatial results tab can be used to create art.
enter link description here http://michaeljswart.com/wp-content/uploads/2010/02/venus.png
EXCEPT and INTERSECT
Instead of writing elaborate joins and subqueries, these two keywords are a much more elegant shorthand and readable way of expressing your query's intent when comparing two query results. New as of SQL Server 2005, they strongly complement UNION which has already existed in the TSQL language for years.
The concepts of EXCEPT, INTERSECT, and UNION are fundamental in set theory which serves as the basis and foundation of relational modeling used by all modern RDBMS. Now, Venn diagram type results can be more intuitively and quite easily generated using TSQL.
I know it's not exactly hidden, but not too many people know about the PIVOT command. I was able to change a stored procedure that used cursors and took 2 minutes to run into a speedy 6 second piece of code that was one tenth the number of lines!
useful when restoring a database for Testing purposes or whatever. Re-maps the login ID's correctly:
EXEC sp_change_users_login 'Auto_Fix', 'Mary', NULL, 'B3r12-36'
Drop all connections to the database:
Use Master
Go
Declare #dbname sysname
Set #dbname = 'name of database you want to drop connections from'
Declare #spid int
Select #spid = min(spid) from master.dbo.sysprocesses
where dbid = db_id(#dbname)
While #spid Is Not Null
Begin
Execute ('Kill ' + #spid)
Select #spid = min(spid) from master.dbo.sysprocesses
where dbid = db_id(#dbname) and spid > #spid
End
Table Checksum
Select CheckSum_Agg(Binary_CheckSum(*)) From Table With (NOLOCK)
Row Checksum
Select CheckSum_Agg(Binary_CheckSum(*)) From Table With (NOLOCK) Where Column = Value
I'm not sure if this is a hidden feature or not, but I stumbled upon this, and have found it to be useful on many occassions. You can concatonate a set of a field in a single select statement, rather than using a cursor and looping through the select statement.
Example:
DECLARE #nvcConcatonated nvarchar(max)
SET #nvcConcatonated = ''
SELECT #nvcConcatonated = #nvcConcatonated + C.CompanyName + ', '
FROM tblCompany C
WHERE C.CompanyID IN (1,2,3)
SELECT #nvcConcatonated
Results:
Acme, Microsoft, Apple,
If you want the code of a stored procedure you can:
sp_helptext 'ProcedureName'
(not sure if it is hidden feature, but I use it all the time)
A stored procedure trick is that you can call them from an INSERT statement. I found this very useful when I was working on an SQL Server database.
CREATE TABLE #toto (v1 int, v2 int, v3 char(4), status char(6))
INSERT #toto (v1, v2, v3, status) EXEC dbo.sp_fulubulu(sp_param1)
SELECT * FROM #toto
DROP TABLE #toto
In SQL Server 2005/2008 to show row numbers in a SELECT query result:
SELECT ( ROW_NUMBER() OVER (ORDER BY OrderId) ) AS RowNumber,
GrandTotal, CustomerId, PurchaseDate
FROM Orders
ORDER BY is a compulsory clause. The OVER() clause tells the SQL Engine to sort data on the specified column (in this case OrderId) and assign numbers as per the sort results.
Useful for parsing stored procedure arguments: xp_sscanf
Reads data from the string into the argument locations specified by each format argument.
The following example uses xp_sscanf
to extract two values from a source
string based on their positions in the
format of the source string.
DECLARE #filename varchar (20), #message varchar (20)
EXEC xp_sscanf 'sync -b -fproducts10.tmp -rrandom', 'sync -b -f%s -r%s',
#filename OUTPUT, #message OUTPUT
SELECT #filename, #message
Here is the result set.
-------------------- --------------------
products10.tmp random
Return Date Only
Select Cast(Floor(Cast(Getdate() As Float))As Datetime)
or
Select DateAdd(Day, 0, DateDiff(Day, 0, Getdate()))
dm_db_index_usage_stats
This allows you to know if data in a table has been updated recently even if you don't have a DateUpdated column on the table.
SELECT OBJECT_NAME(OBJECT_ID) AS DatabaseName, last_user_update,*
FROM sys.dm_db_index_usage_stats
WHERE database_id = DB_ID( 'MyDatabase')
AND OBJECT_ID=OBJECT_ID('MyTable')
Code from: http://blog.sqlauthority.com/2009/05/09/sql-server-find-last-date-time-updated-for-any-table/
Information referenced from:
SQL Server - What is the date/time of the last inserted row of a table?
Available in SQL 2005 and later
Here are some features I find useful but a lot of people don't seem to know about:
sp_tables
Returns a list of objects that can be
queried in the current environment.
This means any object that can appear
in a FROM clause, except synonym
objects.
Link
sp_stored_procedures
Returns a list of stored procedures in
the current environment.
Link
Find records which date falls somewhere inside the current week.
where dateadd( week, datediff( week, 0, TransDate ), 0 ) =
dateadd( week, datediff( week, 0, getdate() ), 0 )
Find records which date occurred last week.
where dateadd( week, datediff( week, 0, TransDate ), 0 ) =
dateadd( week, datediff( week, 0, getdate() ) - 1, 0 )
Returns the date for the beginning of the current week.
select dateadd( week, datediff( week, 0, getdate() ), 0 )
Returns the date for the beginning of last week.
select dateadd( week, datediff( week, 0, getdate() ) - 1, 0 )
Not so much a hidden feature but setting up key mappings in Management Studio under Tools\Options\Keyboard:
Alt+F1 is defaulted to sp_help "selected text" but I cannot live without the adding Ctrl+F1 for sp_helptext "selected text"
Persisted-computed-columns
Computed columns can help you shift the runtime computation cost to data modification phase. The computed column is stored with the rest of the row and is transparently utilized when the expression on the computed columns and the query matches. You can also build indexes on the PCC’s to speed up filtrations and range scans on the expression.
Link
There are times when there's no suitable column to sort by, or you just want the default sort order on a table and you want to enumerate each row. In order to do that you can put "(select 1)" in the "order by" clause and you'd get what you want. Neat, eh?
select row_number() over (order by (select 1)), * from dbo.Table as t
Simple encryption with EncryptByKey