Daily Archives: June 7, 2016

Impala Conditions with Example Impala supports the following conditional functions for testing equality, comparison operators, and nullity: ‘Case’ Example: 1)  If else select case when 20 > 10 then 20 else 15 end; Output:  20 2) If else if select case when 9 > 10 then 20 when 1 > […]

Impala Miscellaneous Functions

PMD (Programming Mistake Detector) What is PMD? PMD aka Programming Mistake Detector is Java Source Code Analyzer. It is used to clean erroneous code in our java projects based on predefined set of rules. PMD supports the ability to write custom rules. Issues reported by PMD may not be true […]

PMD (Programming Mistake Detector)

 Installing the UDF Development Package [crayon-5e88ca481bc01269553160/] The output will be like below code. [cloudera@quickstart impala-udf-samples-master]$ cmake . — The C compiler identification is GNU 4.4.7 — The CXX compiler identification is GNU 4.4.7 — Check for working C compiler: /usr/bin/cc — Check for working C compiler: /usr/bin/cc — works — […]

Creating UDF and UDAF for Impala

CREATE [crayon-5e88ca481c64c904059123/] We can see our new table by typing this: [crayon-5e88ca481c655595809943/] List of relations Schema |    Name    | Type  |  Owner ——–+————+——-+———- public | playground | table | postgres (1 row) INSERT [crayon-5e88ca481c658274308997/]   Message returned if only one row was inserted. oid is the numeric OID of the […]

Postgres Commands

To install the server locally use the command line and type [crayon-5e88ca481ce22689431867/] To start off, we need to set the password of the PostgreSQL user (role) called “postgres”; we will not be able to access the server externally otherwise. As the local “postgres” Linux user, we are allowed to connect […]

Postgres Installation On Centos