yii2 active record query - activerecord

I need to make query (in search model) where:
Get current row index (not id)
Do a manipulation with that count (multiply this on constant number) and add if condition (if 'row index' > 10)
See this count in the model
Some steps I resolve:
I know how to create 'new column' and see it in the gridview:
$query->select([
'{{tour}}.*',
'(1000 / 'need to add row index' ) as points' //$points
]);
I know how to get a current index, but with active record:
MyModel::find()->andFilterWhere(['>=', 'cumulative_points', $playerPoints])->count();
But I need to combine this query. Anybody can help me?
Thanks.

When you need you can express the content of SQL part like literal and then assign the select content you prefer (not using array / hash assignment) this way
$query->select(' tour.*, 1000 / id ) as points' )
Sostantially you can assign to activeQuery select() method exactly the select part of you query ..
http://www.yiiframework.com/doc-2.0/guide-db-query-builder.html

Related

New column indicating if row is the first instance of the value for the Entity ID using SQL instead of DAX

I currently have a column that is created using the following DAX formula (a calculating language used by platforms such as Power BI) which indicates if the listed activity is the first one ever for that Entity ID. Below is my DAX script if it helps at all:
// "Declares column name"
First Time Activity =
// "if the column 'Timestamp' is equal to..."
if('Activity Table'[Timestamp]=
// "...is equal to the earliest Timestamp for that Entity ID and Activity Name"
CALCULATE(min('Activity Table'[Timestamp]),
filter('Activity Table',
'Activity Table'[Entity ID] = earlier('Activity Table'[Entity ID]) &&
'Activity Table'[Activity Name] = earlier('Activity Table'[Activity Name])
)
)
// "...then return a 1. If not, then return a blank/null"
,1,BLANK())
But I need this now to be a column made in PL SQL rather than in DAX. Any help on the SQL script would be much appreciated since I'm fairly novice at SQL.
Thanks
You don't actually need a column. you can write your query as :
Select a
,decode(activity_date
,MIN(activity_date) over (partition by activity_id)
,'Y'
,'N') first_record_indicator
From activity_table a
But, if you table is too huge to actually query like this everytime, you can create a column named first_record_indicator and populate it in "BEFORE INSERT" trigger.
e.g. https://www.techonthenet.com/oracle/triggers/before_insert.php

Strange behaviour when using FILTER to filter a different table with no direct relationship?

I have two facts tables, First and Second, and two dimension tables, dimTime and dimColour.
Fact table First looks like this:
and facet table Second looks like this:
Both dim-tables have 1:* relationships to both fact tables and the filtering is one-directional (from dim to fact), like this:
dimColour[Color] 1 -> * First[Colour]
dimColour[Color] 1 -> * Second[Colour]
dimTime[Time] 1 -> * First[Time]
dimTime[Time] 1 -> * Second[Time_]
Adding the following measure, I would expect the FILTER-functuion not to have any affect on the calculation, since Second does not filter First, right?
Test_Alone =
CALCULATE (
SUM ( First[Amount] );
First[Alone] = "Y";
FILTER(
'Second';
'Second'[Colour]="Red"
)
)
So this should evaluate to 7, since only two rows in First have [Alone] = "Y" with values 1 and 6 and that there is no direct relationship between First and Second. However, this evaluates to 6. If I remove the FILTER-function argument in the calculate, it evaluates to 7.
There are thre additional measures in the pbix-file attached which show the same type of behaviour.
How is filtering one fact table which has no direct relationship to a second fact table affecting the calculation done on the second table?
Ziped Power BI-file: PowerBIFileDownload
Evaluating the table reference 'Second' produces a table that includes the columns in both the Second table, as well as those in all the (transitive) parents of the Second table.
In this case, this is a table with all of the columns in dimColour, dimTime, Second.
You can't see this if you just run:
evaluate 'Second'
as when 'evaluate' returns the results to the user, these "Parent Table" (or "Related") columns are not included.
Even so, these columns are certainly present.
When a table is converted to a row context, these related columns become available via RELATED.
See the following queries:
evaluate FILTER('Second', ISBLANK(RELATED(dimColour[Color])))
evaluate 'Second' order by RELATED(dimTime[Hour])
Similarly, when arguments to CALCULATE are used to update the filter context, these hidden "Related" columns are not ignored; hence, they can end up filtering First, in your example. You can see this, by using a function that strips the related columns, such as INTERSECT:
Test_ActuallyAlone = CALCULATE (
SUM ( First[Amount] ),
First[Alone] = "Y",
//This filter now does nothing, as none of the columns in Second
//have an impact on 'SUM ( First[Amount] )'; and the related columns
//are removed by the INTERSECT.
FILTER(
INTERSECT('Second', 'Second')
'Second'[Colour]="Red"
)
)
(See these resources that describe the "Expanded Table"
(this is an alternative but equivalent explanation of this behaviour)
https://www.sqlbi.com/articles/expanded-tables-in-dax/
https://www.sqlbi.com/articles/context-transition-and-expanded-tables/
)

How to filter clickhouse table by array column contents?

I have a clickhouse table that has one Array(UInt16) column. I want to be able to filter results from this table to only get rows where the values in the array column are above a threshold value. I've been trying to achieve this using some of the array functions (arrayFilter and arrayExists) but I'm not familiar enough with the SQL/Clickhouse query syntax to get this working.
I've created the table using:
CREATE TABLE IF NOT EXISTS ArrayTest (
date Date,
sessionSecond UInt16,
distance Array(UInt16)
) Engine = MergeTree(date, (date, sessionSecond), 8192);
Where the distance values will be distances from a certain point at a certain amount of seconds (sessionSecond) after the date. I've added some sample values so the table looks like the following:
Now I want to get all rows which contain distances greater than 7. I found the array operators documentation here and tried the arrayExists function but it's not working how I'd expect. From the documentation, it says that this function "Returns 1 if there is at least one element in 'arr' for which 'func' returns something other than 0. Otherwise, it returns 0". But when I run the query below I get three zeros returned where I should get a 0 and two ones:
SELECT arrayExists(
val -> val > 7,
arrayEnumerate(distance))
FROM ArrayTest;
Eventually I want to perform this select and then join it with the table contents to only return rows that have an exists = 1 but I need this first step to work before that. Am I using the arrayExists wrong? What I found more confusing is that when I change the comparison value to 2 I get all 1s back. Can this kind of filtering be achieved using the array functions?
Thanks
You can use arrayExists in the WHERE clause.
SELECT *
FROM ArrayTest
WHERE arrayExists(x -> x > 7, distance) = 1;
Another way is to use ARRAY JOIN, if you need to know which values is greater than 7:
SELECT d, distance, sessionSecond
FROM ArrayTest
ARRAY JOIN distance as d
WHERE d > 7
I think the reason why you get 3 zeros is that arrayEnumerate enumerates over the array indexes not array values, and since none of your rows have more than 7 elements arrayEnumerates results in 0 for all the rows.
To make this work,
SELECT arrayExists(
val -> distance[val] > 7,
arrayEnumerate(distance))
FROM ArrayTest;

PowerBi DAX equivalent for SUMIFS with current row value as filter

In Excel I could, if I was in a table called 'Sales' that had four columns
Sales
Month, CustomerId, ProductId, TotalQuantity
Jan,1, CAR,
Feb,1, CAR,
I could add a formula:
=SUMIFS(Sales[Quantity],Sales[CustomerId],[#[CustomerId]])
That would go to the Sales table and sum the CustomerID column filtered by the CustomerID of the current row where the formula has been entered.
I am attempted to replicate this in a PowerBI Calculated Row but I can't get the # working for a row reference. It comes across like
TotalQuantity = CALCULATE(SUM(Sales[Quantity]),Sales[CustomerId] = Sales[CustomerId]))
Any idea how to get the equivalent # working?
I think the key function you are missing is EARLIER. That is not surprising because it has a misleading name - it really means "Current Row". You also need a FILTER function in the Filter parameter of CALCULATE, to reset the filter context to the entire table.
So your New Column function might look like this:
TotalQuantity = CALCULATE(SUM(Sales[Quantity]), FILTER(Sales, Sales[CustomerId] = EARLIER (Sales[CustomerId])))
Here's a neat example, from the most accessible source site for DAX formulas:
http://www.powerpivotpro.com/2013/07/writing-a-subtotal-calc-column-aka-the-simplest-use-of-the-earlier-function/
And FWIW here is the official doco on EARLIER:
https://msdn.microsoft.com/en-us/library/ee634551.aspx

set filter to - INLIST - Visual Foxpro 7

I am working on some legacy code, and I have the following wonderful issue. I am hoping some FoxPro experts can help!
The infrastructure of this legacy system is setup so that I have to use the built-in expression engine to return a result set, so no go on the SQL (i know that would be so much easier!)
Here is the issue.
I need to be able to do something like
PUBLIC ARRAY(20) ArrayOfValuesToFilterBy
SELECT dataTable
SET FILTER TO logicalField = .T. and otherField NOT INLIST(ArrayOfValuesToFilterBy)
However, I know this wont work, I just need the equivalency...not using SQL.
I can generate the list of values to filter by via SQL, just not the final record select due to the legacy infrastructure constraint.
Thanks!
First, a logical field you do not have to do explicit
set filter to Logicalfield = .t.
you can just do
set filter to LogicalField
or
set filter to NOT LogicalField
Next, on the array. VFP has a function ASCAN() which will scan an array for a value, if found, will return the row number within the array that matches what you are looking for.
As for arrays... ex:
DIMENSION MyArray[3]
MyArray[1] = "test1"
MyArray[2] = "something"
MyArray[3] = "anything else"
? ASCAN( MyArray, "else" ) && this will return 0
? ASCAN( MyArray, "anything else" ) && this will return 3
If you are doing a "set filter", the array needs to be "in scope" for the duration of the filter. If you set filter in a procedure the array exists, leave the procedure and the array is gone, you're done.
So, you could do
set filter to LogicalField and ASCAN( YourArray, StringColumnFromTable ) > 0
Now, if you want a subset to WORK WITH, you can do a SQL-Select and pull the data into a CURSOR (temporary read-write table) that has the same capabilities of the original table (except auto-increment when adding)...
I typically name my temporary cursors prefixed with "C_" for "CURSOR OF" so when I'm working with tables, I know if its production data, or just available for temp purposes for quicker display, presentation, extractions from other origins as needed.
use in select( "C_FinalRecords" )
select * from YourTable ;
where LogicalField ;
and ASCAN( YourArray, StringColumnFromTable ) > 0;
into cursor C_FinalRecords READWRITE
Then, you can just use that...
select C_FinalRecords
scan
do something with the record, or values of it...
endscan
or.. bind to a grid in a form, etc...
The INLIST() function takes an expression to search for and up to 24 expressions of the same data type to search.
SELECT dataTable
SET FILTER TO logicalField = .T. AND NOT INLIST(otherField, 'Value1', 'Value2', 'Value3', 'Value4')
I am making some assumptions here, that what you want to do is create a filter with a dynamic in list statement ? If this is correct have a play with this example :-
lcList1="ABCD"
lcList2="EFGH"
lcList3="IJKL"
lcList4="MNOP"
lcList5="QRST"
lcFullList=""
lcFullList=lcFullList+"'"+lcList1+"',"
lcFullList=lcFullList+"'"+lcList2+"',"
lcFullList=lcFullList+"'"+lcList3+"',"
lcFullList=lcFullList+"'"+lcList4+"',"
lcFullList=lcFullList+"'"+lcList5+"'"
lcField="PCode"
lcFilter="SET FILTER TO INLIST ("+lcField+","+lcFullList+")"
The results of the above would create the following filter statement and store it in lcFilter
SET FILTER TO INLIST (PCode,'ABCD','EFGH','IJKL','MNOP','QRST')
you can then use macro substitution
Select dataTable
&lcFilter
Bear in mind that there is likely to be some limitations on how many items you can define in a INLIST() statement

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