These videos were created by Allan Wrobel (Consulting Software Engineer). Allan has been working in the IT industry his entire adult life and has been an employee with LexisNexis Risk Solutions Group since 2010.
How to...
How to...
Use Macros
Use ECL Macros Session 1- A worked through case A explanation of ECL (Enterprise Control Language) MACROS using a real life case study. Compare attributes between two key build where the number of attributes is so large that using MACROS is the only solution.
Be clear about the context in which the ECL FUNCTIONMACROs run Demonstrates that ECL FUNCTIONMACROs compile in the context of the caller and not in the context of the ECL in which the FUNCTIONMACRO resides. There is, at yet, no equivalent of C++ of this in ECL that enables access to an instances variables/state.
ITERATE Processes all records in the recordset one pair of records at a time, performing the transform function on each pair in turn.
PROCESS (Part 1) Processes all records in the recordset one pair of records at a time, performing the datasettransform function on each pair of records in turn.
PROCESS (Part 2) Processes all records in the recordset one pair of records at a time, performing the datasettransform function on each pair of records in turn.
GRAPH A useful and underused function allowing you to search a dataset with different attributes/dimensions which have multiple values. Code examples for this tip can be found in the related HPCC Systems Tips and Trick Forum post.
NORMALIZE (COUNT Variant) This is the simplest of the 2 NORMALIZE functions. This variant is used to call a TRANSFORM repeatedly for each record in a dataset. An interesting use of the NORMALIZE function can also be found in the HPCC Systems ECL Programmer's Guide.
NORMALIZE (Additional Information) Find out more about some additional items such as using child datasets inside child datasets and the behaviour of SKIP.
DENORMALIZE (Single Record Presentation Variant) The inverse to NORMALIZE. This variant covers where inputs are presented singularly to the TRANSFORM. This video also mentions some subtleties of the behaviour of this function.
DENORMALIZE (GROUP Presentation Variant) The inverse to NORMALIZE for child datasets. This variant covers when Child records are presented as DATASETs to the TRANSFORM.
ROLLUP (Part 1) Allows you to deduplicate records with the additional facility to capture information from input records while deduplicating the same.
ROLLUP (Part 2) Follows on from part 1 in this series covering how to preserve the information from one record to the next between iterations and while deduping.
DEDUP The DEDUP function evaluates the recordset for duplicate records, as defined by the condition parameter, and returns a unique return set
Understand the differences Between Build and definition files in HPCC Systems To anyone new to HPCC Systems and the ECL language, the way HPCC Systems behaves differently with the two concepts of Actions and Definitions can be very confusing. Learn about the behavior used with both and find out more about why HPCC Systems runs this way.
Explicit return types from functions Find out how defaulting return types form functions degrades the compilers ability to correctly report errors.
Use ECL/HPCC Systems Events, Including Scheduling Events Demonstration of creating, fielding and firing events in HPCC Systems. Also includes some additional notes on scheduling events (CRON), including reading the output of one workunit in another.
Use ECL Watch Advanced Search Examines some of the advanced functionality built into the ECL Watch Global Search box. Demonstrates how to use prefixes to filter for file types, and navigate to their corresponding pages and show how to filter for specific dates or date ranges