Authentic Snowflake Certification Exam DAA-C01 Questions Answers

To predict future values based on historical data, an analyst must determine the mathematical relationship between two variables—typically time (independent variable) and revenue (dependent variable). This is the foundation of linear regression.

The REGR_SLOPE function is a linear regression function that calculates the slope of the "least squares" regression line for non-null pairs in a group. In the context of sales forecasting, the "slope" represents the rate of change in revenue over time. By calculating the slope, an analyst can project that trend forward to estimate what the revenue will be at a future date (the end of the year).

Evaluating the Options:

Option A (CORR) measures the correlation coefficient, which tells you how strongly two variables are related (between -1 and 1), but it does not provide a mathematical formula to predict a specific future value.

Option C (COVAR_SAMP) calculates the sample covariance, which indicates the direction of a linear relationship but not the magnitude or slope required for prediction.

Option D (VARIANCE) is a descriptive statistic that measures data spread (how far numbers are from the mean) and is not used for trend projection or prediction.

Option B is the 100% correct answer. Along with REGR_INTERCEPT, REGR_SLOPE allows the analyst to build the linear equation $y = mx + b$ to perform predictive analytics.

To determine the correct output, a Data Analyst must understand the behavior of the STRTOK_SPLIT_TO_TABLE table function and how it interacts with different delimiters.

1. Functionality of STRTOK_SPLIT_TO_TABLE:

The STRTOK_SPLIT_TO_TABLE function tokenizes a string based on a set of specified delimiters. Unlike simple SPLIT functions that often look for a literal string as a delimiter, STRTOK treats the delimiter string as a set of individual characters. Any character present in the delimiter string will trigger a split. Crucially, it skips empty tokens—if multiple delimiters appear consecutively, it does not produce a row for the space between them.

2. Evaluating the Data and Delimiters ('*-'):

'JOHN*DOE': The * character is a delimiter. This results in two tokens: JOHN and DOE.

'ALICE-SMITH': The - character is a delimiter. This results in two tokens: ALICE and SMITH.

'BOB*-JOHNSON': Both * and - are delimiters. Because they appear consecutively (*-), the function splits at each but ignores the empty space between them. This results in two tokens: BOB and JOHNSON.

3. Analyzing the Resulting Rows:

The LATERAL join produces a row for every token generated. The columns SEQ (identifying the source row sequence) and INDEX (position of the token within that sequence) are used for sorting.

Student 1: 2 tokens (JOHN, DOE) $\rightarrow$ 2 rows.

Student 2: 2 tokens (ALICE, SMITH) $\rightarrow$ 2 rows.

Student 3: 2 tokens (BOB, JOHNSON) $\rightarrow$ 2 rows.

Evaluating the Options (image_8233d8.png):

Option A incorrectly only shows results for Student 3.

Option C incorrectly implies Student 1 and 2 produce three tokens each.

Option D incorrectly interprets the consecutive delimiters in Student 3's name as creating a different sequence count.

Option B is the 100% correct result set. It accurately shows that each student’s name is split into exactly two parts, properly handling the varying delimiters and the consecutive characters in the third record.

Snowflake Cortex ML functions, such as the Forecasting and Anomaly Detection models, are designed to be "black boxes" that provide automated machine learning capabilities directly within SQL. However, for a Data Analyst to trust and validate these models, Snowflake provides specific Object Methods (invoked with the ! operator) to inspect the model's internal logic and performance.

The !EXPLAIN_FEATURE_IMPORTANCE() method is specifically designed to provide transparency into how the model reached its conclusions. When invoked on a trained forecast model, it returns a result set showing which features (such as exogenous variables or time-based components like seasonality and trend) had the most significant impact on the predicted values. This is a critical step in the Data Analysis workflow to ensure that the model is not relying on "noise" or irrelevant data points.

Evaluating the Options:

Option A (SHOW_EVALUATION_METRICS) is used to retrieve accuracy statistics like MSE (Mean Squared Error) or MAPE (Mean Absolute Percentage Error) from the training phase, but it does not explain the contribution of specific features.

Option B (SHOW_TRAINING_LOGS) is not a standard Cortex ML method; logging details are typically handled internally or through different system views.

Option D (FORECAST) is the primary method used to actually generate the future predictions once the model is trained; it outputs the forecast itself, not the underlying component importance.

Option C is the correct answer as it is the dedicated method for model interpretability, allowing analysts to see the "why" behind the forecast by quantifying the influence of each input variable. This aligns with Snowflake's focus on "Explainable AI" within the Data Cloud.