Can we use convert(int,Employeenumber) function in ColdFusion query of query feature? When I try it I am getting some error.
I am getting records from a stored procedure. When I try to re-query those records with a query of query, using the convert() function, it is throwing an error.
Actually the column is of type varchar and I want to convert that column into an int. Then I want to order by that column, but it is not working. Here is the QofQ:
<cfquery name="qEmployees" dbtype="query">
Select convert(int,employeenumber) as employeenumber
...
</cfquery>
From Conversation:
CONVERT() is usually language-dependent SQL, whereas CAST() is a more general method of essentially doing the same thing, but in this case, it's also what the QoQ engine chose to use.
It's important to remember that the version of SQL in ColdFusion Query of Query is not the same as traditional SQL.There are a lot of things you can't do with a Query of Query, and I definitely wouldn't recommend it for large initial data sets, since it's an in-memory operation.
Also, this issue doesn't appear to be a data type conversion issue. It seems to be an issue with NULL in the data. ColdFusion, especially anything older than the ACF 2018 version, doesn't play nice with NULLs. QoQ doesn't have an ISNULL() or COALESCE() functionality and work-arounds would probably be more trouble than they're worth. The easiest thing would be to modify the original base query to return the needed values.
Related
Up front: this isn't about PowerBI tiles or bringing visualizations into PowerApps. There is a PowerBI data connector that provides a method called ExecuteDatasetQuery that allows for passing in a DAX query for, ostensibly, returning the data from a published dataset. It takes three parameters: workspaceGuid, datasetGuid, and queryText (with an optional object for serializer settings).
There is no query I can send this thing that doesn't return a giant empty table and I have no idea what I'm doing wrong. My queries, which work fine in other systems that do the same thing (JavaScript API calls, PowerAutomate, PowerBI Desktop), all produce a table with no columns and no values in those columns but with a number of rows equal to the rows I'd expect to get back from a query. The result, viewed in PowerApps, looks like this:
And, just for fun, I've converted the return to a JSON string and can confirm that the return is...
just empty. I can find no documentation of merit for the PowerBI connector or this method, so no luck there. Just wondered if anyone's had any experience with this thing and can maybe point me in the right direction. For reference, the query I'm trying to pass in (that works everywhere else) is:
DEFINE
VAR _reqs = SELECTCOLUMNS(MyTable,
"ReqNum",[Title],
"BusinessArea",[BusinessArea],
"Serial1",[Serial1],
"Serial2",[Serial2],
"Department",[Department],
"OM",[OM],
"Requestor",[Requestor],
"StrategicObjective",[ITStrategicObjective],
"Area",[Area],
"ProductLine",[ProductLine],
"ProjectManager",[ProjectManager],
"BusinessLiaison",[BusinessLiaison],
"Customer",[Customer],
"SolutionArchitect",[SolutionArchitect],
"VicePresident",[VicePresident],
"Created",DATEVALUE([Created])
)
EVALUATE
_reqs
ORDER BY
[Created] DESC
But the PowerApps method returns the same empty table even with something as simple as EVALUATE(MyTable).
To protect against sql injection, I read in the introduction to ColdFusion that we are to use the cfqueryparam tag.
But when using stored procedures, I am passing my variables to corresponding variable declarations in SQL Server:
DROP PROC Usr.[Save]
GO
CREATE PROC Usr.[Save]
(#UsrID Int
,#UsrName varchar(max)
) AS
UPDATE Usr
SET UsrName = #UsrName
WHERE UsrID=#UsrID
exec Usr.[get] #UsrID
Q: Is there any value in including cfSqlType when I call a stored procedure?
Here's how I'm currently doing it in Lucee:
storedproc procedure='Usr.[Save]' {
procparam value=Val(form.UsrID);
procparam value=form.UsrName;
procresult name='Usr';
}
This question came up indirectly on another thread. That thread was about query parameters, but the same issues apply to procedures. To summarize, yes you should always type query and proc parameters. Paraphrasing the other answer:
Since cfsqltype is optional, its importance is often underestimated:
Validation:
ColdFusion uses the selected cfsqltype (date, number, etcetera) to validate the "value". This occurs before any sql is ever sent to
the database. So if the "value" is invalid, like "ABC" for type
cf_sql_integer, you do not waste a database call on sql that was never
going to work anyway. When you omit the cfsqltype, everything is
submitted as a string and you lose the extra validation.
Accuracy:
Using an incorrect type may cause CF to submit the wrong value to the database. Selecting the proper cfsqltype ensures you are
sending the correct value - and - sending it in a non-ambiguous format
the database will interpret the way you expect.
Again, technically you can omit the cfsqltype. However, that
means CF will send everything to the database as a string.
Consequently, the database will perform implicit conversion
(usually undesirable). With implicit conversion, the interpretation
of the strings is left entirely up to the database - and it might
not always come up with the answer you would expect.
Submitting dates as strings, rather than date objects, is a
prime example. How will your database interpret a date string like
"05/04/2014"? As April 5th or a May 4th? Well, it depends. Change the
database or the database settings and the result may be completely
different.
The only way to ensure consistent results is to specify the
appropriate cfsqltype. It should match the data type of the target
column/function (or at least an equivalent type).
I have my own data store mechanism for store data. but I want to implement standards data manipulation and query interface for end users,so I thought QT sql is suitable for my case.
but I still cannot understand how do I involved my indexes for sql query.
let say for example,
I have table with column A(int),B(int),C(int),D(int) and column A is indexed.assume I execute query like select * from Foo where A = 10;
How do I involved my index for search the results?.
You have written your own storage system and want to manipulate it using an SQL like syntax? I don't think Qt SQL is the right tool for that job. It offers connectivity to various SQL servers and is not meant for parsing SQL statements. Qt expects to "pass through" the queries and then somehow parse the result set and transform it into a Qt friendly representation.
So if you only want to have a Qt friendly representation, I wouldn't see a reason to go the indirection with SQL.
But regarding your problem:
In SQL, indexes are usually not stated in the queries, but during the creation of the table schema. But SQL server has a possibility to "hint" indexes, is that what you are looking for?
SELECT column_list FROM table_name WITH (INDEX (index_name) [, ...]);
Given a query (pseudo-code):
<cfquery name="myquery">SELECT * FROM stuff</cfquery>
How do I get rid of the first record? In this case, altering the SQL is not an option.
I have tried: myquery.RemoveRows(0,1); but received an error:
No matching Method/Function for Query.REMOVEROWS(numeric, numeric) found
I'm on Railo 3 BTW
Lo and behold:
myquery.RemoveRow(1);
Does exactly what I wanted. Leave it to Railo to do things a little differently!
Can't think of a way offhand to remove a row from the original object. Two things I can think of are:
do a query of queries. That assumes you'd be able to identify the records you don't want and specify them in the WHERE.
construct a new query with queryNew(). Loop over the original query doing a querySetCell() into the new query for the records that you want. This functionality could be incorporated into a UDF pretty easily. In fact, stating that made me think to check cflib.org. See #3
Check cflib.org :) See http://www.cflib.org/udf/QueryDeleteRows
"RemoveRows" is actually a call to the underlying Java method, so you have to cast those numbers. like so:
myquery.RemoveRows(
JavaCast( "int", 0 ) // starting row, zero-based
,JavaCast( "int", 1 ) // number to delete, returns error if too many
)
So probably the method is "int,int", and if you don't cast it, it looks like "numeric,numeric". One might argue that this is undocumented, but it's so succinct that you could (as I did) wrap it in a function, so that if it changes you just need to replace the contents of the function with an alternative workaround.
Railo has added removeRows, see here. My ACF code that uses this method now runs on Railo too, no changes.
With this, the Railo implementation now matches ACF. (Note also that the original Railo implementation was 0 based, while the new one and the ACF version are both 1 based.)
The way I would normally do it is with a query of queries such as the following:
SELECT * FROM myquery
LIMIT {1,10000}
That should work in Railo. What it does is offset the query by one and pulls 10000 records.
You could also do this:
SELECT * FROM myquery
WHERE {primarykey} <> {value}
Where it selects all records except for the primary key value that you pass in.
The awesome thing about ColdFusion is that there are tons of ways to do exactly what you are looking for.
You could just skip the row when you process the results:
<cfoutput query="myquery">
<cfif myquery.currentrow GT 1>
<!---Do the work here. --->
</cfif>
</cfoutput>
I need to make a query like this:
SELECT PNPDeviceID FROM Win32_NetworkAdapter WHERE AdapterTypeId = 0
Trouble is, the AdapterTypeId column isn't always present. In this case, I just want everything, like so:
SELECT PNPDeviceID FROM Win32_NetworkAdapter
My WQL/SQL knowledge is extremely limited. Can anybody tell me how to do this in a single query?
EDIT:
A bit more background seems to be required: I am querying Windows for device information using WMI, which uses an SQL-like syntax. So, in my example, I am querying for network adapters that have an AdapterTypeId of 0.
That column is not always present however, meaning that if I enumerate through the returned values then "AdapterTypeId" is not listed.
EDIT 2:
Changed SQL to WQL; apparantly this is more correct.
I am assuming you mean the underlying schema is unreliable.
This is a highly unconventional situation. I suggest that you resolve the issue that is causing the column to not always be present, because to have the schema changing dynamically underneath your application is potentially (almost certainly) disastrous.
Update:
OK, so WQL lets you query objects with a SQL-like syntax but, unlike SQL, the schema can change underneath your feet. This is a classic example of a leaky abstraction, and I now hate WQL without ever having used it :).
Since the available properties are in flux, I am guessing that WQL provides a way to enumerate the properties for a given adapter. Do this, and choose which query to run depending upon the results.
After some Googling, there is an example here, which shows how to enumerate through the available properties. You can use this to determine if AdapterTypeId exists or not.
SELECT PNPDeviceID FROM Win32_NetworkAdapter WHERE AdapterTypeId = {yourDesire} OR AdapterTypeId IS NULL
I assume that you mean that this field is missing from the table.
Do you know before submitting the query if this field exists?
If yes then just create SQL dynamically, otherwise It think you will get syntax error in case of missing field
This is not an SQL question. SQL does not contemplate records with varying schemas in a single table source. Instead (as you mention) this is a different system using an "SQL-like" syntax. You'll have better luck if you recast the question using the actual product that you're trying to query, and information how that product deals with variable record structures is probably discussed in the documentation.