Databricks ML Associate Domains Explained

The short version

The exam has four sections: Databricks Machine Learning (38%), ML Workflows (19%), Model Development (31%), and Model Deployment (12%). The first section is the most platform-specific, and it is also the largest. The weightings come from Databricks’ certification page, and the objectives come from its exam guide, the version live as of March 1, 2025. Both were read on October 18, 2026. The typical traps below are our own explanatory notes, not vendor statements.

One naming detail: the certification page calls section 2 “ML Workflows,” while the exam guide titles the section holding data exploration and preparation objectives “Data Processing.” The objectives listed under it are about data preparation, and that is what we describe here.

Section 1: Databricks Machine Learning (38%)

What it covers. The platform itself. The guide lists MLOps best practices, the advantages of ML runtimes, how AutoML helps with model and feature selection, and what AutoML brings to model development. Then feature tables: the benefits of creating them in Unity Catalog compared with the workspace level, creating one, writing data to it, training a model with its features, scoring a model with its features, and online versus offline tables. Then MLflow: identifying the best run with the client API, manually logging metrics, artifacts, and models, reading the MLflow UI, registering a model in the Unity Catalog registry, and why that beats the workspace registry. Finally: setting or removing a model tag, promoting a challenger to a champion with aliases, and when to promote code instead of a model.

In practice. This is the daily workflow of a team that wants repeatable machine learning. You build features once in a governed table, train from them, log everything, register the winner, and point an alias at it so that serving code picks up the right version.

Typical traps.

  • Mixing up writing modes on a feature table. A partial batch that should update only some keys is a merge, not an overwrite.
  • Treating logging and registering as one step. They are separate.
  • Forgetting that a metric logged repeatedly needs a step value to keep its history.
  • Picking “promote the model” by reflex. If the production data cannot leave production, the code moves instead and the model is trained there.
  • Confusing an offline table (for training and batch scoring) with an online store (for low-latency lookups).

What to practice. Create a feature table, write to it, build a training set, and train. Log a run by hand, register the model, set a tag, and move an alias from one version to another.

Section 2: ML Workflows, also called Data Processing (19%)

What it covers. Summary statistics on a Spark DataFrame with `.summary()` or dbutils data summaries. Removing outliers by standard deviation or IQR. Visualizing categorical and continuous features, and picking the right method to compare two categorical or two continuous features. Imputing missing values with the mean, median, or mode, and the trade-offs between them. One-hot encoding, including the model types and data sets where it does or does not fit. Knowing when a log-scale transformation is appropriate.

In practice. The unglamorous but large part of any project. Before training, you look at distributions, handle gaps and extreme values, and encode categories so that an algorithm can use them.

Typical traps.

  • Using the mean on a skewed column when the median is more robust.
  • Using the mean or median on a nominal column. A country code needs the mode.
  • One-hot encoding an ordered column, which throws the order away.
  • Applying a log to values that can be zero or negative.
  • Forgetting that filling many rows with one value shrinks the spread of a column.

What to practice. Run summaries on a DataFrame and read them. Remove outliers with both rules. Impute with each statistic and compare the effect on the distribution. Draw a box plot and a histogram of the same column and note what each shows.

Section 3: Model Development (31%)

What it covers. Choosing an algorithm for a scenario. Methods to mitigate imbalanced training data. Estimators versus transformers, and building a training pipeline. Tuning: Hyperopt’s `fmin`, random, grid, and Bayesian search, and parallelizing single-node models for tuning. Cross-validation, including its benefits and downsides compared with a train-validation split, performing it during fitting, and counting how many models a grid search with cross-validation trains. Metrics: F1, log loss, ROC/AUC, RMSE, MAE, R-squared, and choosing the right one for an objective. Exponentiating log-transformed variables before calculating metrics or interpreting predictions. Model complexity and the bias-variance trade-off.

In practice. Training, but with discipline. You pick a metric that matches the business cost, tune on validation data only, and keep a held-out check on the result.

Typical traps.

  • Reporting accuracy on an imbalanced data set, where precision, recall, F1, or AUC say more.
  • Comparing an error computed on a log scale with one computed on the raw scale.
  • Miscounting models: combinations in the grid multiplied by folds. Read the grid carefully, and check whether the question counts a final refit.
  • Assuming parallel hyperparameter trials also distribute the training itself.
  • Mixing up which one is larger, RMSE or MAE, and why (RMSE is never smaller).
  • Treating estimators and transformers as interchangeable. An estimator learns with `fit`, a transformer applies with `transform`.

What to practice. Build a pipeline that imputes, encodes, and trains. Run a small grid with cross-validation and count the fits. Compare metrics on a skewed data set. Run a Hyperopt search and look at the trials.

Section 4: Model Deployment (12%)

What it covers. The differences and advantages of batch, real-time, and streaming serving. Deploying a custom model to an endpoint. Batch inference with pandas. Streaming inference with Delta Live Tables. Deploying and querying a model for real-time inference. Splitting traffic between endpoints.

In practice. Matching the delivery style to the need. A nightly report is batch. A checkout screen needs a real-time endpoint. A continuous event feed may be scored inside a streaming pipeline.

Typical traps.

  • Choosing a real-time endpoint when nobody needs an answer within seconds.
  • Ignoring cost and latency trade-offs, such as the slow first request after an idle endpoint scales to zero.
  • Forgetting that traffic shares must add up to the whole.
  • Missing that the stem says “already running a pipeline,” which points to scoring inside it.

What to practice. Deploy one model to an endpoint, query it, and change the traffic split. Score a table in batch.

Where the points are

Section 1 and Section 3 together are 69% of the exam. If your time is short, put it there, and use Sections 2 and 4 to pick up the points that are quick to learn.

Next step

Take the study plan and fit these sections to your calendar. When you want questions on each section, try the Databricks ML Associate practice tests.

Frequently asked questions

Which section should I study first?

Section 1 if you are new to Databricks, since the others build on feature tables, MLflow, and the registry. Start with Section 3 if you know the platform but not machine learning.

Is Spark ML on the exam?

The guide mentions working knowledge of SparkML and scikit-learn, and several objectives (pipelines, estimators, transformers, tuning) apply to both.

Do I need to memorize API syntax?

Not word for word, but you should recognize the right method or argument when you see it.