DEA-C01 Data Ingestion and Transformation Practice Question
A data engineer is building an AWS Glue ETL job that reads a large JDBC table from Amazon RDS for PostgreSQL. The job must read the table in parallel to reduce runtime, but the table has no numeric primary key or monotonically increasing column. Which AWS Glue connection property should the engineer configure to enable parallel reads?
⚠ Common exam trap
The trap here is assuming that partitionColumn with lowerBound and upperBound always works for parallel JDBC reads, when it actually requires a numeric, evenly distributed column.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
hashpartitions and hashfield
For JDBC sources without a numeric or monotonic column, AWS Glue provides hashpartitions and hashfield to enable parallel reads. hashpartitions sets the number of partitions, and hashfield names a column used for hashing rows across those partitions. This avoids the need for a numeric partitionColumn and is the documented approach for this exact situation.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
partitionColumn with lowerBound and upperBound
Why it's wrong here
partitionColumn, lowerBound, and upperBound are the standard JDBC parallel read properties, but they require a numeric column with evenly distributed values. The scenario explicitly states the table has no numeric primary key or monotonic column, so this approach cannot be used. Choosing this option ignores the stated constraint and would result in either a serial read or an error if the column is not numeric.
- ✗
hashfield
Why it's wrong here
The hashfield property is used with hashpartitions to define a custom hashing partition column for JDBC reads. It requires a column suitable for hashing, but the scenario explicitly states no numeric or monotonic column exists. While hashfield can use non-numeric columns in some cases, it still needs a column with sufficient distinct values and is not the standard answer for tables lacking a suitable partitioning column. It does not solve the core problem of enabling parallel reads without a key.
- ✓
hashpartitions and hashfield
Why this is correct
AWS Glue supports hashpartitions and hashfield connection options specifically for JDBC sources that lack a suitable numeric partitioning column. hashpartitions defines the number of parallel read partitions, and hashfield specifies a column (often a string or UUID) used to hash rows into those partitions. This enables parallel reads without requiring a numeric key, directly addressing the scenario's constraint.
- ✗
enableParallelRead with numPartitions
Why it's wrong here
enableParallelRead and numPartitions are not valid AWS Glue JDBC connection properties. While numPartitions appears in some Spark JDBC configurations, AWS Glue uses different property names. This option is a plausible-sounding but incorrect combination that would not enable parallel reads. The engineer must use the actual Glue-supported properties, which are hashpartitions and hashfield for non-numeric columns.
Go deeper
Related to this question
About these practice questions
Courseiva writes every DEA-C01 question from scratch — 1,321 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Amazon Web Services exam blueprint
This DEA-C01 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DEA-C01 exam.