I have a scenario where I need to filter out those records in which few NUMBER columns have zero as its value.
Say record 1 contains: c1_amount= 5, c2_amount=-2, c3_amount=-3 and other columns are having zeroes.
Here, the following code fails, as it will filter out the records which is not exactly what I want because 3 columns has non zero values but after sum resulting zero.
Select * from table where
( C1_amount+
C2_amount+
.
.
.
C50_amount) <>0;
I am little concerned about performance. That is the reason why I neither want to use abs() on all 50 column nor check every column <> 0.
Try to select like
SELECT * FROM Table WHERE
decode(c1_amount,0,0,1)+decode(c2_amount,0,0,1)+..
..+decode(c50_amount,0,0,1)>0
or use ALL
SELECT * FROM Table WHERE
0!=ANY(c1_amount,...,c50_amount)
Related
I'm developing an application that uses a tabular database to show some business data.
I need to provide some basic filtering over measures values (equal to, greater than, lesser than etc.) and I'm currently analyzing the proper way to generate the MDX.
Looking at some documentation (and other threads on this site), I found that the most efficient approach would be using the FILTER or HAVING functions to filter out undesired values.
Unfortunately all examples normally include measures on one axis and dimension member on the other, but I potentially have dimension members in both axis and can't find a proper solution to use such functions to filter by measure value.
What have I done so far?
To make it easier to explain, let's say that we want to get the yearly sales quantities by product class filtering quantity > 1.3 milions
Trying to use HAVING or FILTER Functions, the resulting MDX I came up with is
SELECT
NON EMPTY {[YearList].[Year].[Year].MEMBERS * [Measures].[Qty]}
HAVING [Measures].[Qty] > 1.3e6 ON COLUMNS,
NON EMPTY {[Classes].[cClass].[cClass].MEMBERS}
HAVING [Measures].[Qty] > 1.3e6 ON ROWS
FROM [Model]
or
SELECT
NON EMPTY FILTER({[YearList].[Year].[Year].MEMBERS * [Measures].[Qty]},
[Measures].[Qty] > 1.3e6) ON COLUMNS,
NON EMPTY FILTER({[Classes].[cClass].[cClass].MEMBERS} ,
[Measures].[Qty] > 1.3e6) ON ROWS
FROM [Model]
But this is of course leading to unexpected result for the final user because the filter is happening on the aggregation of the quantities by the dimension on that axis only, which is greater then 1.3M
The only way I found so far to achieve what I need is to define a custom member with an IIF statement
WITH
MEMBER [Measures].[FilteredQty] AS
IIF ( [Measures].[Qty] > 1.3e6, [Measures].[Qty], NULL)
SELECT
NON EMPTY {[YearList].[Year].[Year].MEMBERS * [Measures].[FilteredQty]} ON COLUMNS,
NON EMPTY {[Classes].[cClass].[cClass].MEMBERS} ON ROWS
FROM [Model]
The result is the one expected:
Is this the best approach or I should keep using FILTER and HAVING functions? Is there even a better approach I'm still missing?
Thanks
This is the best approach. You need to consider how MDX resolves result. In the example above it is a coincidence that your valid data in a continous region of first four columns of first row. Lets relax the filtering clause and make it >365000. Now take a look at last row of the result, the first two columns and the last column are eligible cells but the third and fourth column is not eligible. However your query will report it as null and the non empty function will not help. The reason is that non empty needs the entire row to be null
Now the question that why filter is not eliminating the cell? Filter will eliminate a row or column when the criteria is greater then the sum on the other axis. So if filter is on columns the filter value has to be greater than the sum of rows for that column. Take a look at the sample below as soon as you remove the comments the last column will be removed.
select
non empty
filter(
([Measures].[Internet Sales Amount]
,{[Date].[Calendar Year].&[2013],[Date].[Calendar Year].&[2014]}
,[Date].[Calendar Quarter of Year].[Calendar Quarter of Year]
),([Date].[Calendar Year].currentmember,[Date].[Calendar Quarter of Year].currentmember,[Product].[Subcategory].currentmember,[Measures].[Internet Sales Amount])>45694.70--+0.05
)
on columns
,
non empty
[Product].[Subcategory].members
on rows
from
[Adventure Works]
Edit another sample added.
with
member [Measures].[Internet Sales AmountTest]
as
iif(([Date].[Calendar Year].currentmember,[Date].[Calendar Quarter of Year].currentmember,[Product].[Subcategory].currentmember,[Measures].[Internet Sales Amount])>9000,
([Date].[Calendar Year].currentmember,[Date].[Calendar Quarter of Year].currentmember,[Product].[Subcategory].currentmember,[Measures].[Internet Sales Amount]),
null
)
select
non empty
({[Measures].[Internet Sales Amount],[Measures].[Internet Sales AmountTest]}
,{[Date].[Calendar Year].&[2013]}
,[Date].[Calendar Quarter of Year].[Calendar Quarter of Year]
)
on columns
,
non empty
[Product].[Subcategory].[Subcategory]
on rows
from
[Adventure Works]
I have a table with two columns(Using oracle 11g database) : Country, IndexNumber. Table contains 10 rows(10 different cities and with its unique index number.)
For example:
Country IndexNUmber
India 1
Australia 2
. .
. .
. .
. .
US 10
Now i want to fetch a random row from above table by generating random number using dbms_random.value(1,10). To achieve that i am using below query:
select * from tab_name where indexnumber = dbms_random.value(1,10);
I am not able to understand the output of this query as some time it is fetching one row, some time zero rows and some time more that one row.
Can someone please make me understand how oracle is evaluating this query.
Thanks
Ankit
Since dbms_random.value is a nondeterministic PL/SQL function, it will be called once for each row evaluated by the query.
The function might return 4 when evaluating the first row, then it might return 8 on the second row, etc.
To compare each row to a single random number, you can turn the function call into a scalar subquery, e.g.:
select * from tab_name where indexnumber = (select dbms_random.value(1,10) from dual);
Since the subquery is not correlated to the main query, Oracle will execute it only once (for the first row returned from the table) and remember the result for all subsequent rows. In particular, if a suitable index is on indexnumber the query will be able to use it more efficiently since it knows it is probing for a single value.
When you run your original query:
select * from tab_name where indexnumber = dbms_random.value(1,10);
it appears that the call to dbms_random is happening for each record's where clause. In other words, there is a chance that every record in your table might be returned if the random number chosen happen to match the index for every record. If you want to retrieve a single random record, then follow this pattern:
select *
from
( select * from tab_name order by DBMS_RANDOM.VALUE )
where rownum < 2;
In SSAS, I wanted to create a measure that counts the number of rows which the column values contains a specific string.
eg. table
|Id|item
|1|greenapple
|2|blueapple2
|3|yellowapple
|4|purplegrape
search for "apple".
i want the measure return 3.
how should i write the DAX expression?
thanks.
Step 1 first add a column in your table
AppleFlag := if(SEARCH("apple",Table1[Name],1,0)>0,1,0)
Step 2 then create Measure
Apple Count := SUM(Table1[AppleFlag])
I am building stacked column flash chart on my query. I would like to split values in column for different locations. For argument sake I have 5 ids in location 41, 3 ids in location 21, 8 ids in location 1
select
'' link,
To_Char(ENQUIRED_DATE,'MON-YY') label,
count(decode(location_id,41,id,0)) "location1",
count(decode(location_id,21,id,0)) "location2",
count(decode(location_id,1,id,0)) "location3"
from "my_table"
where
some_conditions = 'Y';
as a result of this query Apex is creating stacked column with three separate parts( hurray!), however it instead of having values 5,3 and 8, it returns three regions 16,16,16. ( 16 = 5 +3+8).
So obviously Apex is going through all decode conditions and adding all values.
I am trying to achieve something described in this
article
Apex doesn't appear to be doing anything funky, you'd get the same result running that query through SQL*Plus. When you do:
count(decode(location_id,41,id,0)) "location1",
.. then the count gets incremented for every row - it doesn't matter which column you include, and the zero is just treated as any fixed value. I think you meant to use sum:
sum(decode(location_id,41,1,0)) "location1",
Here each row is assigned either zero or one, and summing those gives you the number that got one, which is the number that had the specified id value.
Personally I'd generally use caseover decode, but the result is the same:
sum(case when location_id = 41 then 1 else 0 end) "location1",
While looking at the following answer I wanted to replace the range with a filter.
MDX - Concurrent calculations based on a "record time range"?
The MDX is:
with member [Measures].[TotalUsed] as sum({[Date].[YQM].&[20090501]:[Date].[YQM].&[20090907]}, [Measures].[Used])
select {[Measures].[Total Used]}on columns,
{[Color].[Colors].[All].MEMBERS}on rows
from [Cube]
I'm trying to replace the Date range with a filter like this:
with member [Measures].[TotalUsed] as sum(FILTER([Date].[YQM], [Date].[YQM] < [Date].[YQM].&[20090907]), [Measures].[Used])
select {[Measures].[Total Used]}oncolumns,
{[Color].[Colors].[All].MEMBERS}on rows
from [Cube]
What is the conditional statement looking for in terms of comparing values? Any Help would be great!
Thanks!
The Filter statement needs a SET and then an EXPRESSION to filter on. You can drop this right inside your SUM function. The expression part of the filter can be almost anything, but it has to evaulate to true/false for each cell in the SET.
-- FILTER ( SET, EXPRESSION)
It's a bit tough not knowing what your data is structured like but your statment would probably end up like the following, filtering rows with less than 50 'UnUsed' for your timeperiods, and then summing them as an example.
`
WITH MEMBER [Measures].[TotalUsed]
AS SUM (FILTER ( [Date].[YQM].members, [Measures].[UnUsed] > 50 ),
[Measures].[Used] )
SELECT {[Measures].[Total Used]} ON COLUMNS,
{[Color].[Colors].[All].MEMBERS} ON ROWS
FROM [Cube]