It is useful to be able to quickly understand the details of the analytical view, and its SQL definition.
Consider the SQL form of the analytical views that we built in the earlier steps.
Clicking the Detail link opens the AV Details window modal, that shows all the information about the analytical view, including Score Detail, Base Table Info, AView Info, and Aview SQL.
Please note that the SQL expression of the analytical view cannot be changed. Instead, you must create a new analytical view with an updated definition.
To examine the details of analytical view geo.national_geo_features_av_1
,
click Details.
The first time you examine the analytical view, you may have to run statistics to determine an accurate rating.
In the AV Details window modal, under the Score Detail tab, click Run Compute Statistics Once.
After statistical computations complete, you can examine the components of AV details:
Similarly, look at the SQL statement that represents the second analytical view,
geo.national_geo_features_av_1
, by clicking Show
SQL.
Consider and compare the two statements:
geo.geo_features_lv_av_1
is an analytical view created over a logical view
SELECT TA_0.feature_class Feature_Class, TA_0.state_alpha State_Alpha, sum_no_finalize(1) Record_Count FROM geo.geo_features_lv TA_0 GROUP BY 1, 2
geo.national_geo_features_av_1
is an analytical view created over a base table
SELECT TA_0.feature_class Feature_Class, TA_0.county_name County_Name, sum_no_finalize(1) Record_Count, TA_0.state_alpha State_Alpha FROM geo.national_geo_features TA_0 GROUP BY 1, 2, 4
TA_0
is the automatically generated alias for the base table or logical view.
It is not the same entity in these two statements.
sum_no_finalize(1)
is the function that returns record count.The Score Detail explains the rating of the analytical view:
Analytical views are always in parquet format. If original data is not in parquet format, then converting to an analytical view applies parquet's default compression techniques.
Join computations are cached, eliminating the need to perform join computations after query routing.
Aggregation functions can result in data reduction. Analytical views cache the results after aggregation, eliminating to perform these computations after query routing.
If analytical views are partitioned, they can be incrementally refreshed. Only the partitions containing stale data will be refreshed, leaving the valid partitions untouched.
The following elements indicate how Arcadia Engine determines the score of the analytical view:
This number is 5.
This number is subtracted from the maximum score.
This number represents the final rating after applying deductions.
This tab details the information about the base table of the analytical view.
database_name.table_name
TEXT
, PARQUET
, or
KUDU
This tab lists the information about the analytical view.
database_name.aview_name
PARQUET
This tab provides the definition of the analytical view.
database_name.aview_name
sum(1)
SELECT
statement that defines the analytical view