I have a table and want to know the best way to see if there had been any data changes to one particular column, and if so, I would want to get an email alert - if that is possible.
My idea is to create a base table that only has this column with the data, lets say its called 'mytable'. The column is 'Reporting_code'
Then every day I would do a select distinct for this column in the main table. If the value is new or changed it would display it.
Select distinct reporting_code a from Prod_table where reporting_code a not in
(select distinct reporting_code b from mytable)
But is there a better way to be doing this?
Related
background
I am trying to create an SSRS report which will run select * on a table passed in as a parameter and display all the data from that table. As I understand it, I can't use a table for this. I want to use a pivot table to achieve this.
select * from #table will return something like this (from the adventureworks DB)
I want to display the date in this format:
Question
How do I achieve this? I looked at using PIVOT/UNPIVOT, but all the examples I've seen use static column names and aggregates.
I won't know the column names at design time (or run time), I'm assuming I will need column headers like 'table name', 'value1', 'value2' etc?
Limitations
I won't have access to create stored procedures. Ideally, the report should be able to be run entirely from SSRS without having to create new tables etc.
Performance is not a concern.
Edit
Editing to add some clarity. The column names in the example above are only an example. The #table parameter could be any table, column names won't be know at design time. The column names could be col1, col2, or name, address... etc.
You can do this with a normal tablix, with a column group on BusinessEntityID
Create a normal tablix.
Remove the row group (group only)
Insert a new parent column group, grouped by BusinessEntityID
Delete the top row (row only)
Add each of the row titles in, as per your suggested output
Add each of the values in the second column
What would be the expression to create a calculated column in Table Example 2 called "SZODMAXCALC", that would contain the SZODMAXCALC from Table Example 1 given that the data from Table Example 1 falls between the dates (DTTMSTART and DTTMEND) within Table Example 2?
Maybe this is easier done on the SQL side that loads the data?
there is no way to create a calculated column that references a column in another table.
you will need to do a join either in Spotfire (via Insert...Columns)* or on the SQL-side of things (either via a view on your database or by creating a new information link in Spotfire).
the best method depends on your data structure, implementation, and desired results, so I'm not able to recommed there. take a look at both options and evaluate which one works best.
* NOTE that Spotfire cannot join based on a Calculated Column as a common key. that is, using your example, if [WELLNAME] is a calculated column, you cannot tell Spotfire the equivalent of SELECT wellname, ... FROM table_a LEFT JOIN table_b ON table_a.wellname = table_b.wellname.
the alternative is to Insert...Transformation and choose Insert New Calculated Column, and to join on that instead.
the reason for this is that calculated columns are very mutable; they could change frequently based on a user action. it would be inefficient to re-execute the join each time the column's contents changed. conversely, a "Transformation Calculated Column" is only updated when the data table is loaded.
I'm wondering if it's possible to check to see if a row exists in a table, if it does not I want to see if it exists in another. I am happy to either know if there is simply a row or the actual row details.
My example is as follows:
I have a list of players, they can be authorised to be in a team or be temporarily in a team. I've got 2 tables which are identical in data structure:
PlayerList
id, team_ref, player_ref
PlayerListTemp
id, team_ref, player_ref
I want to first check if they are in the temp table, if not check to see if they are in the normal table. If neither exist I want to allow them to be picked.
EXISTS is your friend
Assuming your selecting from a table (whatever in my example) which contains the player player_ref:
SELECT *
FROM wherever
WHERE NOT EXISTS(SELECT 1 FROM PlayerList WHERE player_ref=whatever.player_ref)
AND NOT EXISTS(SELECT 1 FROM PlayerListTemp WHERE player_ref=whatever.player_ref)
I have been struggling with creating a query in Access to select a distinct field with the criteria of having the newest entry in the database.
Heres a brief summary of how what my table conssists of. I have a table with surveying data collected from 2007 to the present. We have field with a survey marks name with corresponding adjustment data. In the corresponding data there is field with the adjusmtent date. Many of the marks have been occupied mutiple times and only want to retrieve the most recent occupation information.
Roughly i want to
SELECT DISTINCT STATUS_POINT_DESIGNATION
FROM __ALL_ADJUSTMENTS
WHERE [__ALL_ADJUSMENTS]![ADJ_DATE]=MAX(ADJ_DATE)
I seem to be getting confused how relate the select a distinct value with a constraint. Any Suggestions?
DH
Seems you could achieve your aim of getting the latest observation for each survey point by a summary function:
SELECT STATUS_POINT_DESIGNATION, Max(ADJ_DATE) AS LatestDate, Count(STATUS_POINT_DESIGNATION) AS Observations
FROM __ALL_ADJUSTMENTS
GROUP BY STATUS_POINT_DESIGNATION;
What would be the correct universal SQL construct to get the last row inserted (or it's primary key). The ID might be autogenerated by a sequence but I do not want to deal with the sequence at all! I need to get the ID by querying the table. Alternatively, INSERT might be somehow extended to return the ID. Assume I am always inserting a single row. The solution should work with most RDBMS!
the best way is to depend on the sequence like:
select Max(ID) from tableName
but If you don't want to deal with it, you can add new timestamp column to your table and then select max from that column.
like this way
select Max(TimestampField) from tableName