HCL Technologies Data Engineer Interview Guide

The HCL Technologies data engineer loop, round by round: what each stage tests, example questions with the guidance interviewers actually score, the mistakes that sink strong candidates, and how to prepare.

Last updated: July 31, 2026Proudly published by: Jeff Wahl

Try a HCL Technologies-style SQL round

Find every user active on 3 or more CONSECUTIVE days. This gaps-and-islands shape shows up in nearly every DE SQL round. Edit the query and run it against the seed data.

	/* Users active on 3+ consecutive days. */
	/* Hint: date minus a per-user ROW_NUMBER is constant within a streak. */
	WITH streaks AS (
	SELECT
	user_id,
	activity_date,
	activity_date - CAST(
	(ROW_NUMBER() OVER (
	PARTITION BY user_id
	ORDER BY activity_date
	))
	AS INT
	) AS grp
	FROM user_sessions
	)

	SELECT
	user_id
	FROM streaks
	GROUP BY user_id, grp
	HAVING COUNT(*) >= 3

HCL Technologies is hiring data engineers now

The roles behind this loop. Prep against the levels and locations they are actually filling.

Hiring now

HCL Technologies data engineer · live from career pages

open roles

San Francisco Bay Area

top metro

Design and develop solutions using Quantexa Decision Intelligence Platform

L4London Area29d ago

Design data ingestion frameworks for batch, micro-batch, and real-time processing.

L4Multiple locations36d ago

Build and govern batch and streaming data pipelines using Auto Loader, Structured Streaming, and Delta Live Tables.

L5New Jersey42d ago

Lead network and security architecture design (HLD/LLD)

L4Toronto52d ago

Build, monitor, and optimize ETL and ELT processes with data models.

L5Plano53d ago

Design, develop, and maintain scalable and reliable data pipelines and data products within the Google Cloud Platform (GCP) ecosystem.

L4Secaucus53d ago

Working knowledge of Azure Data Explorer (Kusto) and Cosmos DB, including query patterns and data modeling.

L5Multiple locations60d ago

Ability to manage several technical workstreams and priorities.

L4London Area65d ago

Knowledge of integrating AI agents with enterprise data platforms for automation and analytics use cases is preferred.

L5Plano71d ago

New postings per week

5/25

6/1

6/8

6/15

6/22

6/29

week beginning · ~6 weeks of data

Where they hire

San Francisco Bay Area

Toronto

Levels hiring

L45L54

Updated Jul 31, 202613 open listings across 2 cities

HCL Technologies compensation and culture

The numbers, tech stack, and team structure live on the company overview.

Data engineering at HCL Technologies→

The role, comp by level, tech stack, teams, and culture signals.

Compare HCL Technologies with other data engineering employers

How the role, pay, and loop stack up against peer companies.

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02 / Why practice

Prepare at HCL Technologies interview difficulty

01
Reading a solution is not the same as writing one
Every engineer who has frozen on a query they had read a dozen times knows the gap. The only preparation that closes it is producing the answer yourself, under time, before the interview does it for you
02
76% of hiring managers reject on the coding task, not the resume
From HackerRank's 2024 Developer Skills Report. Candidates who look strong on paper still fail the live screen if they haven't done timed, executable practice
03
5 problem shapes cover 80% of data engineer loops
Dedup, sessionization, top-N-per-group, slowly-changing dimensions, partition tricks. Writing the shapes by hand turns the unfamiliar into pattern recognition

Practice HCL Technologies-level SQL

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