Cross tab/ Dynamic Pivoting in PostgreSQL - postgresql

I am trying to create a dynamic pivoting in postgresql.
my query is including 3 dimensions in which one includes a case statement. and one measure. I have tried various solutions found on web but none is working. pls help me with this.

Related

HIVE Case Statement: Selecting from another table

I am confused on how to get this to work. I have tried a few different ways to get this to work and I am trying to find the best solution. I have about 10 case statements that need to reference another table for verification. So instead of typing out each exclusion and inclusion I created a table. This works with SAS and works with SQL, though HIVE is the troublemaker.
The CPX.CHP and ONC.ODCD have a list of codes/numbers/etc.
When ((main.refrl_req_by_desc in ('MM', 'HP') AND (main.refrl_req_rsn_desc in ('CCM'))) AND (main.PRIMP = CPX.CHP) AND (main.PRIMD != ONC.ODCD)) then 2
Appreciate any guidance on this.

Converting SQL query with FORMAT command to use in entity framework core

I have an SQL query:
SELECT
FORMAT(datetime_scrapped, 'MMMM-yy') [date],
count(FORMAT(datetime_scrapped, 'MMMM-yy')) as quantity
FROM scrap_log
GROUP BY FORMAT(datetime_scrapped, 'MMMM-yy')
It basically summarises all the entries in the scrap_log table by month/year and counts how many entries are in each month/year. Returns two columns (date and quantity). But I need to execute this in an ASP.NET core API using Entity Framework core. I tried using .fromSqlRaw(), but this expects all columns to be returned and so doesn't work.
I can find plenty of info on EF to implement group by and count etc... But I cannot find anything for the FORMAT(datetime, "MMMM-yy") part. Please could somebody explain to me how to do this?
EDIT: Seems already I appear to be going about this the wrong way in terms of efficiency. I will look into alternative solutions based on comments already made. Thanks for the fast response.

HBase - MultiGet and Selective Columns

I can query using multiget to be able to selectively query multiple random rows from HBase.
http://hostname:port/tablename/multiget/?row=row1&row=row2
For selecting few columns,
http://hostname:port/tablename/rowkey/columnFamily:columnName
How to be able to use multiget and be able to select only few columns at the same time?
Looking at this (HBASE-3541) JIRA issue for multi-gets, it seems like there is no option to specify columns when using multiget. However, it also seems like it would be pretty simple to add this functionality.
EDIT: the issue I opened regarding this problem (linked here) was resolved and included in HBase's 1.3.0 release, and now it is possible to select only specific columns.

Can I have more than 250 columns in the result of a PostgreSQL query?

Note that PostgreSQL website mentions that it has a limit on number of columns between 250-1600 columns depending on column types.
Scenario:
Say I have data in 17 tables each table having around 100 columns. All are joinable through primary keys. Would it be okay if I select all these columns in a single select statement? The query would be pretty complex but can be programmatically generated. The reason for doing this is to get denormalised data to populate a web page. Please do not ask why though :)
Quite obviously if I do create table table1 as (<the complex select statement>), I will be hitting the limit mentioned in the website. But do simple queries also face the same restriction?
I could probably find this out by doing the exercise myself. In the next few days I probably will. However, if someone has an idea about this and the problems I might face by doing a single query, please share the knowledge.
I can't find definitive documentation to back this up, but I have
received the following error using JDBC on Postgresql 9.1 before.
org.postgresql.util.PSQLException: ERROR: target lists can have at most 1664 entries
As I say though, I can't find the documentation for that so it may
vary by release.
I've found the confirmation. The maximum is 1664.
This is one of the metrics that is available for confirmation in the INFORMATION_SCHEMA.SQL_SIZING table.
SELECT * FROM INFORMATION_SCHEMA.SQL_SIZING
WHERE SIZING_NAME = 'MAXIMUM COLUMNS IN SELECT';

Joing several MDX query results in a single report

I use MS SQL Server 2008 R2.
I've got the problem, please, excuse the long explanation.
We've got the SSAS cube. It is under development at this time, but it is partially working and can be accessed through excel.
There are projects: hierarchycal parent-child dimension
There are resources assigned to the project (e.g. man-hours, building materials, technic): dimension with resource types, fact M2M table ProjectId-ResourceId-UnitsCount-Cost
There are milestones for the projects: dimension with milestone types (few are defined), M2M fact table: ProjectId-MilestoneId-...milestone dates: planned/actual start/finish
This is a simplified schema.
I need to create a MS Reporting Services report with the following columns:
Project Hierarchy
several columnts with the pre-defined and "hardcoded" resource type amount. e.g the business wants to see the columnt with man-hours spent, and concrete consumption in cub-meters. Thse two clauses can be hardcoded in the query.
several columns with the pre-defined and "hardcoded" milestone type dates
this is a simplified schema too, more columns with other dimension slices are needed...
The problem is that i cannot find an elegant way to create this report.
in my current version, i have to create 2 datasets and query the resouce and milestone data in separate mdx queries.
then i need to use RS-lookup function to join the data in report outcome.
Please acvise:
is there a possibility to query this data in an single mdx query. when i try something like this:
union({{[Dim Resource].[Measure].[man-hour]} + {[Dim Resource].[Measure].[cub-meter]}},
{[Dim Milestone].[Milestone Type].[ProjectStart]}) i've got "different dimensionality" error. Any workarounds?
if i need to output a formatted value like: "X 'man-hour' / Y 'cub-meter'", i have to use lookup func to get both parts of the formula - any better way?
can i query this data any other way?
Please, indicate the direction of googling
or... should i just query the data from the source tables (this is allowed by security restrictions) with SQL
thank you in advance
Perhaps create a new 'virtual cube' to contain data from both of your existing cubes, then query that one.