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;
Related
I am trying to write a query to find out whether a record exist more than one or not in a given period of time. And even if it exist, how many times the same record has been repeated.
Now to solve this issue, I have sorted the records.
select * from table_name where date = ? and date > ? order by email
And trying to count the number of times the same record exist.But I am not able to figure out a way to count the number of times the same record exists.
Here is a problem.The image below holds the basic data structure.
Here is the expected output for a year
The table above holds Xyz name and xyz#email.com data three times. And the name Abc and email abc#email.com two times and the third record name Def and email def#email.com two times. Now what I am trying to figure out a way to find out the number of times each records are being repeated in a given period of time using a single query. I am thinking to make use of recursion on a record and count till it didn't find a different record after sorting it. But using recursion on every records seems expensive.
Is there a better solution to solve this problem ?
Regards
Group and count.
SELECT column_to_compare1, column_to_compare2, COUNT(*)
FROM table_name
WHERE [date] BETWEEN #date1 AND #date2
GROUP BY column_to_compare1, column_to_compare2
HAVING COUNT(*) > 1 -- IF YOU WANT TO ONLY INCLUDE RECORDS WITH DUPLICATES
Between is inclusive, so you can adjust your dates with DATEADD if you really want between.
You can use the COUNT function to do this.
To do this using your own query:
SELECT Name, Email, COUNT(*) AS count
FROM table_name
WHERE date BETWEEN '01/01/2005' AND '31/12/2005'
GROUP BY Name, Email
However your example query is poor so I cannot give you a better solution. Here is an example of this working: SQL Fiddle
EDIT: Updated my solution to match you expected output.
I have a very large database and I need to extract information from 3 columns:
I am trying to determine how many unique customers the user is processing.
Username. This is unique name.
CustomerNumber. A customer number will appear on many lines, as they could have ordered many products and each product is a line.
Date Range. I need to be able to define a date range.
The code I am tried and searched is counting the customer numbers, but not just the distinct customer number.
I have not tried the date range as yet.
I have attached 2 images to show an example of the database and the end result. We used a pivot table to produce this result, but the data changes all the time and we dont want to create a pivot table the whole time.
Image of Sample Data in Excel:
Image of Required Final Result
SELECT `'All data$'`.Username, Count(`'All data$'`.CustomerNumber)
FROM `C:\Users\rhynto\Desktop\Darren Qwix\QWIX_PICKED.xlsx`.`'All data$'` `'All data$'`
GROUP BY `'All data$'`.Username
I will appreciate any advice on this please.
Here's the scenario:
I have an Access project with tables consisting of the following data:
Activity table: ActivityName, ActivityPopularityRating
Volunteer table: VolunteerName, VolunteerRating
Each activity can have many volunteers and each volunteer has a rating.
I have to create a report which indicates for each activity, the names and ratings of the volunteers taking part in that activity, as well as the average VolunteerRating of the those volunteers taking part in each activity. An example is attached.
I have created the SQL query but I am not sure if I should generate the average value needed in the query, or if there is some function in Access that would allow me to do that in the report.
Here is my Query:
SELECT Activity.ActivityName,
Activity.ActivityPopularityRating,
StudentVolunteer.VolunteerName,
StudentVolunteer.VolunteerRating,
AVG(StudentVolunteer.VolunteerRating)
FROM Activity
INNER JOIN StudentVolunteer ON Activity.ActivityName = StudentVolunteer.ActivityName
GROUP BY Activity.ActivityName
All help is appreciated
Thanks
To add a total line (here showing the average rating) to your results, you would use UNION ALL in MsAccess (or ROLLUP in another DBMS). However, it is not necessary to add such line to your query. The data is already there (it is the avarage of the selected ratings, which can easily be calcualted from them).
So remove GROUP BY and the AVG line from your query and add AVG(VolunteerRating) in your report layer instead. The report will then calculate the avarage from the ratings.
How can i generate an ID value for every set of duplicate records as seen in the second table with ID column? In other words, how can I let the first table to look like the second table using SQL query?
Assume that first name and last name in the first table can appear in duplicates.
Each first name and last name can have one or many purchase yr and cost.
The given image is just a sample. Total records in table 1 can reach thousands.
I'm using Oracle SQL.
Note: I'm working with one table only that is the first one. The second table is what I want.
You can use the DENSE_RANK analytic function to assign ID's as below:
EDIT:
Simplified query to generate ID's.
SELECT
DENSE_RANK() OVER (ORDER BY First_Name, Last_Name) ID,
t.*
FROM Table1 t;
Reference:
DENSE_RANK on Oracle Database SQL Reference
I am trying to develop a SQL Server 2005 query but I'm being unsuccessful at the moment. I trying every different approach that I know, like derived tables, sub-queries, CTE's, etc, but I couldn't solve the problem. I won't post the queries I tried here because they involve many other columns and tables, but I will try to explain the problem with a simpler example:
There are two tables: PARTS_SOLD and PARTS_PURCHASED. The first contains products that were sold to customers, and the second contains products that were purchased from suppliers. Both tables contains a foreign key associated with the movement itself, that contains the dates, etc.
Here is the simplified schema:
Table PARTS_SOLD:
part_id
date
other columns
Table PARTS_PURCHASED
part_id
date
other columns
What I need is to join every row in PARTS_SOLD with a unique row from PARTS_PURCHASED, chose by part_id and the maximum "date", where the "date" is equal of before the "date" column from PARTS_PURCHASED. In other words, I need to collect some information from the last purchase event for the item for every event of selling this item.
The problem itself is that I didn't find a way of joining the PARTS_PURCHASED table with PARTS_SOLD table using the column "date" from PARTS_SOLD to limit the MAX(date) of the PARTS_PURCHASED table.
I could have done this with a cursor to solve the problem with the tools I know, but every table has millions of rows, and perhaps using cursors or sub-queries that evaluate a query for every row would make the process very slow.
You aren't going to like my answer. Your database is designed incorrectly which is why you can't get the data back out the way you want. Even using a cursor, you would not get good data from this. Assume that you purchased 5 of part 1 on May 31, 2010. Assume on June 1, you sold ten of part 1. Matching just on date, you would match all ten to the May 31 purchase even though that is clearly not correct, some parts might have been purchased on May 23 and some may have been purchased on July 19, 2008.
If you want to know which purchased part relates to which sold part, your database design should include the PartPurchasedID as part of the PartsSold record and this should be populated at the time of the purchase, not later for reporting when you have 1,000,000 records to sort through.
Perhaps the following would help:
SELECT S.*
FROM PARTS_SOLD S
INNER JOIN (SELECT PART_ID, MAX(DATE)
FROM PARTS_PURCHASED
GROUP BY PART_ID) D
ON (D.PART_ID = S.PART_ID)
WHERE D.DATE <= S.DATE
Share and enjoy.
I'll toss this out there, but it's likely to contain all kinds of mistakes... both because I'm not sure I understand your question and because my SQL is... weak at best. That being said, my thought would be to try something like:
SELECT * FROM PARTS_SOLD
INNER JOIN (SELECT part_id, max(date) AS max_date
FROM PARTS_PURCHASED
GROUP BY part_id) AS subtable
ON PARTS_SOLD.part_id = subtable.part_id
AND PARTS_SOLD.date < subtable.max_date