August 9, 2012 at 12:19 pm
Hello,
I am new to SQL and have been asked to perform a query of our Dispatch database. Although I am able to pull most of the information I need I am having trouble with the following.
The following queries work seperately on their own:
SELECT unit_status_datetime AS UnitLeftSceneDateTime
FROM unit_status_hist
WHERE cad_command_code = 'EH'
SELECT unit_status_datetime AS UnitLeftSceneDateTime
FROM unit_status_hist
WHERE cad_command_code = 'AH'
Problem is I need to include these in a query that will be selecting multiple columns along with these.
Is there a way to specify multiple aliases for a single column a retrive the data I need?
Thank you for your time!
Chris Abbott
August 9, 2012 at 12:34 pm
I don't understand the problem, but I believe you don't need multiple aliases.
Can you explain in more detail and give the exact problem? Or what do you mean by this:
Problem is I need to include these in a query that will be selecting multiple columns along with these.
August 9, 2012 at 12:45 pm
dirtyshorellc (8/9/2012)
Hello,I am new to SQL and have been asked to perform a query of our Dispatch database. Although I am able to pull most of the information I need I am having trouble with the following.
The following queries work seperately on their own:
SELECT unit_status_datetime AS UnitLeftSceneDateTime
FROM unit_status_hist
WHERE cad_command_code = 'EH'
SELECT unit_status_datetime AS UnitLeftSceneDateTime
FROM unit_status_hist
WHERE cad_command_code = 'AH'
Problem is I need to include these in a query that will be selecting multiple columns along with these.
Is there a way to specify multiple aliases for a single column a retrive the data I need?
Thank you for your time!
Chris Abbott
Not knowing how these are being used in the overall query, hard to give you a working answer.
Looking at these queries as is, the follow are equivalent:
SELECT unit_status_datetime AS UnitLeftSceneDateTime
FROM unit_status_hist
WHERE cad_command_code = 'EH' OR cad_command_code = 'AH';
SELECT unit_status_datetime AS UnitLeftSceneDateTime
FROM unit_status_hist
WHERE cad_command_code in ('EH','AH');
Perhaps if you showed us what it is you are trying to accomplish we could give you a better answer.
August 9, 2012 at 12:52 pm
My appologies.
What I am doing is creating a query that will simply take certain columns from a table and export them to a csv file for export to another server. The export is for EMS calls and the data will include all of the unit status information for the incident. All of the other columns that I need to include in this query I'm able to retrieve with no issue. The problem is that I only need 2 types of data from the column I listed and I need to be able to seperate the retrived data and create a seperate column for each data type in the export file.
Here is what I have so far:
SELECT
incident_num AS IncidentNumber, incident_date AS IncidentDateTime, e911_time AS PsapCallDateTime,
rec_time AS DispatchNotifiedDateTime, disp_time AS UnitNotifiedDispatchDateTime, enr_time AS UnitEnRouteDateTime,
arv_time AS UnitArrivedSceneDateTime,
-- This is where the CAD_COMMAND_CODE for UnitLeftScene and PatientArrivedDest fields will live.
clr_time AS UnitBackInServiceDateTime, location AS StreetAddress, address AS StreetAddress2,
city_code AS City, call_type AS EmdCardNumber, disposition_code AS DestinationCode
FROM
cfs_incident_core
As you can see I am aliasing each column of the table to match the expected format for the other server.
Also I seem to have made a mistake in my first post. Each query should have a different Alias. The query for the 'AH' data should have been aliased as PatientArrivedDestDateTime. Again my apologies!
Also I'm using MS SQL SVR 2000.
August 14, 2012 at 7:27 pm
dirtyshorellc (8/9/2012)
My appologies.What I am doing is creating a query that will simply take certain columns from a table and export them to a csv file for export to another server. The export is for EMS calls and the data will include all of the unit status information for the incident. All of the other columns that I need to include in this query I'm able to retrieve with no issue. The problem is that I only need 2 types of data from the column I listed and I need to be able to seperate the retrived data and create a seperate column for each data type in the export file.
Here is what I have so far:
SELECT
incident_num AS IncidentNumber, incident_date AS IncidentDateTime, e911_time AS PsapCallDateTime,
rec_time AS DispatchNotifiedDateTime, disp_time AS UnitNotifiedDispatchDateTime, enr_time AS UnitEnRouteDateTime,
arv_time AS UnitArrivedSceneDateTime,
-- This is where the CAD_COMMAND_CODE for UnitLeftScene and PatientArrivedDest fields will live.
clr_time AS UnitBackInServiceDateTime, location AS StreetAddress, address AS StreetAddress2,
city_code AS City, call_type AS EmdCardNumber, disposition_code AS DestinationCode
FROM
cfs_incident_core
As you can see I am aliasing each column of the table to match the expected format for the other server.
Also I seem to have made a mistake in my first post. Each query should have a different Alias. The query for the 'AH' data should have been aliased as PatientArrivedDestDateTime. Again my apologies!
Also I'm using MS SQL SVR 2000.
Perhaps something like this?
SELECT unit_status
UnitLeftSceneDateTime=MAX(CASE WHEN cad_command_code = 'EH' THEN unit_status_datetime END)
PatientArrivedDestDateTime=MAX(CASE WHEN cad_command_code = 'AH' THEN unit_status_datetime END)
FROM unit_status_hist
GROUP BY unit_status
My thought question: Have you ever been told that your query runs too fast?
My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.
Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
Since random numbers are too important to be left to chance, let's generate some![/url]
Learn to understand recursive CTEs by example.[/url]
[url url=http://www.sqlservercentral.com/articles/St
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