In some previous posts we demonstrated how to load XML data into an Oracle database using ODI. We first looked at some of the issues when reverse engineering an XSD in ODI. Next we looked at various issues when parsing and processing XML files in ODI. We also showed that Flexter parses XML files without creating a single data flow ...
As of Spark 1.4.0 we now have support for window functions (aka analytic functions) in SparkSQL. At Sonra we are heavy users of SparkSQL to handle data transformations for structured data. We also use it in combination with cached RDDs and Tableau for business intelligence and visual analytics. Spark SQL and Window Functions: The rationale I am a strong supporter ...
Thanks again to everyone who attended the third Hadoop User Group Ireland meetup. Also thanks to Bank of Ireland Grand Canal Square for making the venue available. Participants in the event can send feedback to their Twitter and Facebook accounts: facebook.com/BOIGrandCanalSquare twitter.com/BOIGrandCanalSQ. Also thanks to Étienne from Idiro and Antonio from HP for their great presentations. We have all of ...
Today we will have a look what happens when we place a filter condition into an outer join. We will also have a look at how this compares to placing the filter condition into the WHERE clause. Finally we'll have a look where this could be useful. Let's first create some sample data.
create table customer (
ALTER TABLE customer
add CONSTRAINT pk_customer PRIMARY KEY (cust_id);
create table customer_loc (
ALTER TABLE customer_loc
add CONSTRAINT pk_customer_loc PRIMARY KEY (customer_loc_id);
insert into customer values (1,'Gold');
insert into customer values (2,'Gold');
insert into customer values (3,'Silver');
insert into customer_loc values (1,1,'Dublin');
insert into customer_loc values (2,2,'Paris');
insert into customer_loc values (3,4,'Berlin');
analyze table customer compute statistics;
analyze table customer_loc compute statistics;
Let's run our first outer join ...