Yes, I know this seems simple:
SELECT DISTINCT(...)
Except, it apparently isn't
Here is my actual Query:
SELECT
DeclinationReasons.Reason,
EmployeeInformation.ID,
EmployeeInformation.Employee,
EmployeeInformation.Active,
CompletedTrainings.DecShotDate,
CompletedTrainings.DecShotLocation,
CompletedTrainings.DecReason,
CompletedTrainings.DecExplanation,
IIf([DecShotLocation]="MCS","Yes","No") AS YesMCS,
IIf([DecReason]=1,1,0) AS YesAllergy,
IIf([DecReason]=2,1,0) AS YesImmune,
IIf([DecReason]=3,1,0) AS YesAdverse,
IIf([DecReason]=4,1,0) AS YesMedical,
IIf([DecReason]=5,1,0) AS YesSpiritual,
IIf([DecReason]=6,1,0) AS YesOther,
IIf([DecReason]=7,1,0) AS YesAlready
FROM
EmployeeInformation
INNER JOIN (CompletedTrainings
LEFT JOIN DeclinationReasons ON CompletedTrainings.DecReason = DeclinationReasons.ReasonID)
ON EmployeeInformation.ID = CompletedTrainings.Employee
GROUP BY
DeclinationReasons.Reason,
EmployeeInformation.ID,
EmployeeInformation.Employee,
EmployeeInformation.Active,
CompletedTrainings.DecShotDate,
CompletedTrainings.DecShotLocation,
CompletedTrainings.DecReason,
CompletedTrainings.DecExplanation,
IIf([DecShotLocation]="MCS","Yes","No"),
IIf([DecReason]=1,1,0),
IIf([DecReason]=2,1,0),
IIf([DecReason]=3,1,0),
IIf([DecReason]=4,1,0),
IIf([DecReason]=5,1,0),
IIf([DecReason]=6,1,0),
IIf([DecReason]=7,1,0)
HAVING
((((EmployeeInformation.Active) Like -1)
AND ((CompletedTrainings.DecShotDate + 365 >= DATE())
OR (CompletedTrainings.DecShotDate IS NULL))));
This is Joining a few tables (obviously) in order to get a number of records. The problem is that if someone is duplicated on the table with a NULL in one of the date fields, and a date in another field, it pulls both the NULL and the DATE, or pulls multiple NULLS it might pull multiple dates but those are not present right at the moment.
I need the Nulls, they are actual data in this particular case, but if someone has a date and a NULL I need to pull only the newest record, I thought I could add MAX(RecordID) from the table, but that didn't change the results of the query either.
That code:
SELECT
DeclinationReasons.Reason,
EmployeeInformation.ID,
EmployeeInformation.Employee,
EmployeeInformation.Active,
MAX(CompletedTrainings.RecordID),
CompletedTrainings.DecShotDate
...
And it returned the same issue, Duplicated EmployeeInformation.ID with different DecShotDate values.
Currently it returns:
ID
Active
DecShotDate
etc. x a bunch
1
-1
date date
whatever goes
2
-1
in these
2
-1
date date
columns
These are being used in a report, that is to determine the total number of employees who fit the criteria of the report. The NULLs in DecShotDate are needed as they show people who did not refuse to get a flu vaccine in the current year, while the dates are people who did refuse.
Now I have come up with one simple solution, I could add a column to the CompletedTrainings Table that contains a date or other value, and add that to the HAVING statement. This might be the right solution as this is a yearly training questionnaire that employees have to fill out. But I am asking for advice before doing this.
Am I right in thinking I need to add a column to filter by so that older data isn't being pulled, or should I be able to do this by pulling recordID, and did I just bork that part of the query up?
Edited to add raw table views:
EmployeeInformation Table:
ID
Last
First
empID
Active
Termdate
DoH
Title
PT/FT/PD
PI
1
Doe
Jane
982
-1
date
Sr
PD
X
2
Roe
John
278
0
date
date
Jr
PD
X
3
Moe
Larry
1232
-1
date
Sr
FT
X
4
Zoe
Debbie
1424
-1
date
Sr
PT
X
DeclinationReasons Table:
ReasonID
Reason
1
Allergy
2
Already got it
3
Illness
CompletedTrainings Table:
RecordID
Employee
Training
...
DecShotdate
DecShotLocation
DecShotReason
DecExp
1
1
4
date
location
2
text
2
1
4
3
2
4
4
3
4
date
location
3
text
5
3
4
date
location
1
text
6
4
4
After some serious soul searching, I decided to use another column and filter by that.
In the end my query looks like this:
SELECT *
FROM (
(
SELECT RecordID, DecShotDate, DecShotLocation, DecReason, DecExplanation, Employee,
IIf([DecShotLocation]="MCS","Yes","No") AS YesMCS, IIf([DecReason]=1,1,0) AS YesAllergy,
IIf([DecReason]=2,1,0) AS YesImmune, IIf([DecReason]=3,1,0) AS YesAdverse,
IIf([DecReason]=4,1,0) AS YesMedical, IIf([DecReason]=5,1,0) AS YesSpiritual,
IIf([DecReason]=6,1,0) AS YesOther, IIf([DecReason]=7,1,0) AS YesAlready
FROM CompletedTrainings WHERE (CompletedDate > DATE() - 365 ) AND (Training = 69)) AS T1
LEFT JOIN
(
SELECT ID, Active FROM EmployeeInformation) AS T2 ON T1.Employee = T2.ID)
LEFT JOIN
(
SELECT Reason, ReasonID FROM DeclinationReasons) AS T3 ON T1.DecReason = T3.ReasonID;
This may not have been the best solution, but it did exactly what I needed. Which is to get the information by latest entry into the database.
Previously I had tried to use MAX(), DISTINCT(), etc. but always had a problem of multiple records being retrieved. In this case, I intentionally SELECT the most recent records first, then join them to the results of the next query, and so on. Until I have all the required data for my report.
I write this in hopes someone else finds it useful. Or even better if someone tells me why this is wrong, so as to improve my own skills.
I am using influxDB and I would like to extract some values which is greater than certain threshold in other table.
For example, I have two tables as shown in below.
Table A
Time value
1 15
2 25
3 9
4 22
Table B
Time threshold
1 16
2 12
3 13
4 15
Give above two tables, I would like to extract three values which is greater than first row in Table B. Therefore what I want to have is as below.
Time value
2 25
4 22
I tried it using below sql query, but it didn't give any correct result.
select * from data1 where value > (select spec from spec1 limit1);
Look forward to your feedback.
Thanks.
Integrate the condition in an inner join:
select * from tableA as a
inner join tableB as b on a.id=b.id and a.value > b.threshold
When your time column doesn't only include integer values, you have to format the time and join on a time range. Here is an example:
SQL join on time range
I have a requirement wherein i need to find the record number of the records that are returned from the resultset. I know that i can use ROWNUM to get the record number from the resultset but my issue is slightly different. below are the details
Table : ProcessSummary
Columns:
PS_PK ProcessId StepId AsscoiateId ProcessName AssetAmount
145 25 50 Process1 3,500.00
267 26 45 Process2 4,400.00
356 27 70 Process3 2,400.00
456 28 80 90 Process4 780.00
556 29 56 67 Process5 4,500.00
656 45 70 Process6 6,000.00
789 31 75 Process7 8,000.00
Now what i need to do is fetch all the records from the ProcessSummary Table when either of ProcessId OR StepId OR AssociateId is NULL. I wrote the below query
select * from ProcessSummary where ProcessId IS NULL OR StepId IS NULL OR AsscoiateId IS NULL
As expected i got 1st, 2nd, 3rd, 6th and 7th records in the resultset that got returned.
Now what i need is to get the records numbers 1,2,3,6,7. I tried to use the ROWNUM as below but i got the values of 1,2,3,4,5 and not 1,2,3,6,7.
select ROWNUM from ProcessSummary where ProcessId IS NULL OR StepId IS NULL OR AsscoiateId IS NULL
Is it possible to get the ROWNUM values in the sequence that i want and if yes then can you please let me know how can i do this. Also if ROWNUM cannot be used then what would be the other option that i can use to get the result in the form that i want.
Any help would be greately appericiated as i could not find much on the net or SO regarding this sort of requirement.
Thanks
Vikeng21
rownum is an internal numbering that gives you a row number based on the current query results only, so that numbering is not tied to a specific record, and it will change when you change the data or the query.
But the numbering you ask for is already in your table. It looks like you just need to SELECT PS_PK .. instead. PS_PK is the field in your table that contains the actual number you want.
You can generate a numbering using an analytical function, and then filter that query. You need some fields to order by, though. In this case I've chosen PS_PK, but it can be another field, like ProcessName or a combination of other fields as well.
select
*
from
(select
dense_rank() over (order by PS_PK) as RANKING,
p.*
from
ProcessSummary p)
where
ProcessId IS NULL OR StepId IS NULL OR AsscoiateId IS NULL
So, in this query, first a numbering is calculated for each row that is returned from the inner query. The numbering is returned as the field RANKING. And then the other query filters further, but still will return the field RANKING with the original numbering.
Instead of dense_rank there is also rank and row_number. The differences are subtle, but you can just experiment and read some docs here and here to learn about the differences and see which one fits you best.
Note that this might slow down your query, because the inner query first generates a number for each row in the table (there is no filtering on that level now).
In my table, I have data that looks like this:
CODE DATE PRICE
100 1/1/13 $500
100 2/1/13 $521
100 3/3/13 $530
100 5/9/13 $542
222 3/3/13 $20
350 1/1/13 $200
350 3/1/13 $225
Is it possible to create query to pull out the TWO most recent records by DATE? AND only if there are 2+ dates for a specific code. So the result would be:
CODE DATE PRICE
100 5/9/13 $542
100 3/3/13 $530
350 3/1/13 $225
350 1/1/13 $200
Bonus points if you can put both prices/dates on the same line, like this:
CODE OLD_DATE OLD_PRICE NEW_DATE NEW_PRICE
100 3/3/13 $530 5/9/13 $542
350 1/1/13 $200 3/1/13 $225
Thank you!!!
I managed to solve it with 5 sub-queries and 1 rollup query.
First we have a subquery that gives us the MAX date for each code.
Next, we do the same subquery, except we exclude our previous results.
We assume that your data is already rolled up and you won't have duplicate dates for the same code.
Next we bring in the appropriate Code / Price for the latest and 2nd latest date. If a code doesn't exist in the 2nd Max query - then we don't include it at all.
In the union query we're combining the results of both. In the Rollup Query, we're sorting and removing null values generated in the union.
Results:
CODE MaxOfOLDDATE MaxOfOLDPRICE MaxOfNEWDATE MaxOfNEWPRICE
100 2013-03-03 $530.00 2013-05-09 542
350 2013-01-01 $200.00 2013-03-01 225
Using your Data in a table called "Table", create the following queries:
SUB_2ndMaxDatesPerCode:
SELECT Table.CODE, Max(Table.Date) AS MaxOfDATE1
FROM SUB_MaxDatesPerCode RIGHT JOIN [Table] ON (SUB_MaxDatesPerCode.MaxOfDATE = Table.DATE) AND (SUB_MaxDatesPerCode.CODE = Table.CODE)
GROUP BY Table.CODE, SUB_MaxDatesPerCode.CODE
HAVING (((SUB_MaxDatesPerCode.CODE) Is Null));
SUB_MaxDatesPerCode:
SELECT Table.CODE, Max(Table.Date) AS MaxOfDATE
FROM [Table]
GROUP BY Table.CODE;
SUB_2ndMaxData:
SELECT Table.CODE, Table.Date, Table.PRICE
FROM [Table] INNER JOIN SUB_2ndMaxDatesPerCode ON (Table.DATE = SUB_2ndMaxDatesPerCode.MaxOfDATE1) AND (Table.CODE = SUB_2ndMaxDatesPerCode.Table.CODE);
SUB_MaxData:
SELECT Table.CODE, Table.Date, Table.PRICE
FROM ([Table] INNER JOIN SUB_MaxDatesPerCode ON (Table.DATE = SUB_MaxDatesPerCode.MaxOfDATE) AND (Table.CODE = SUB_MaxDatesPerCode.CODE)) INNER JOIN SUB_2ndMaxDatesPerCode ON Table.CODE = SUB_2ndMaxDatesPerCode.Table.CODE;
SUB_Data:
SELECT CODE, DATE AS OLDDATE, PRICE AS OLDPRICE, NULL AS NEWDATE, NULL AS NEWPRICE FROM SUB_2ndMaxData;
UNION ALL SELECT CODE, NULL AS OLDDATE, NULL AS OLDPRICE, DATE AS NEWDATE, PRICE AS NEWPRICE FROM SUB_MaxData;
Data (Rollup):
SELECT SUB_Data.CODE, Max(SUB_Data.OLDDATE) AS MaxOfOLDDATE, Max(SUB_Data.OLDPRICE) AS MaxOfOLDPRICE, Max(SUB_Data.NEWDATE) AS MaxOfNEWDATE, Max(SUB_Data.NEWPRICE) AS MaxOfNEWPRICE
FROM SUB_Data
GROUP BY SUB_Data.CODE
ORDER BY SUB_Data.CODE;
There you go - thanks for the challenge.
Accessing the recent data
To access the recent data, you use TOP 2. Such as you inverse the data from the table, then select the top 2. Just as you start ABC from ZYX and select the TOP 2 which would provide you with ZY.
SELECT TOP 2 * FROM table_name ORDER BY column_time DESC;
This way, you reverse the table, and then select the most recent two from the top.
Joining the Tables
To join the two columns and create a result from there quest you can use JOIN (INNER JOIN; I prefer this) such as:
SELECT TOP 2 * FROM table_name INNER JOIN table_name.column_name ON
table_name.column_name2
This way, you will join both the tables where a value in one column matches the value from the other column in both tables.
You can use a for loop for this to select the value for them, or you can use this inside the foreach loop to take out the values for them.
My suggestion
My best method would be to, first just select the data that was ordered using the date.
Then inside the foreach() loop where you will write the data for that select the remaining data for that time. And write it inside that loop.
Code (column_name) won't bother you
And when you will reference the query using ORDER By Time Desc you won't be using the CODE anymore such as WHERE Code = value. And you will get the code for the most recent ones. If you really need the code column, you can filter it out using and if else block.
Reference:
http://technet.microsoft.com/en-us/library/ms190014(v=sql.105).aspx (Inner join)
http://www.w3schools.com/sql/sql_func_first.asp (top; check the Sql Server query)
I have an access database that I'm well aware is quite poorly designed, unfortunately it is what I must use. It looks a little like the following:
(Row# is not a column in the database, it's just there to help me describe what I'm after)
Row# ID Date Misc
1 001 01/8/2013 A
2 001 01/8/2013 B
3 001 01/8/2013 C
4 002 02/8/2013 D
5 002 02/8/2013 A
6 003 04/8/2013 B
7 003 04/8/2013 D
8 003 04/8/2013 D
What I'm trying to do is obtain all information entered for the last n (by date) 'entries' where an 'entry' is all rows with a unique ID.
So if I want the last 1 entry I will get rows 6, 7 and 8. The last two entries will get me rows 4-8 etc.
I've tried to get the SN's needed in a subselect and then select all entries where those SN's appear, but I couldn't get it to work. Any help appreciated.
Thanks.
The proper Access syntax:
select *
from t
where ID in (select top 10 ID
from t
group by ID
order by max([date]) desc
)
I think this will work:
select *
from table
where Date in (
select distinct(Date) as unique_date from table order by unique_date DESC limit <num>
)
The idea is to use the subselect with a limit to only identify dates you care about.
EDIT: Some databases do not allow a limit in a subquery (I'm looking at you, mysql). In that case, you'll have to make a temporary table out of the subquery then select * from it.