0.5.1
Released: November 16, 2021
Bug Fixes
Latest Query Name Collisions
The fix enables users to choose whatever column names they would like inside of Latest queries without generating errors.
Symptom
Seeing feature-level errors:
ValidationException: Invalid ProjectionExpression: Attribute name is a reserved keyword; reserved keyword: state
for features defined as Latest queries, e.g.
state := Latest<user_responses>(state by zipcode)
Root Cause
Sumatra's implementation of Latest left open the possibility of name conflicts with DynamoDB's list of reserved words, including "state".
Fix
Use Dynamo's expression attribute aliases to avoid the name collisions.
Spurious Divide By Zero Errors
The fix changes the behavior of the following aggregates to no longer generate errors when aggregating over the empty set:
AverageStdDevMedianMedianAbsoluteDeviation
Symptom
Seeing feature-level errors:
avg_rate_per_zip: divide by zero
for features defined as Average queries, e.g.
avg_rate_per_zip := Average(rate by zip)
and data where rate is null.
Root Cause
Sumatra's implementation of Average and 3 other aggregates reported errors when missing data would result in a divide by zero. This error reporting is unnecessary as the null return value is sufficient.
Fix
The design change was made to return null without error for these 4 aggregates when aggregating over empty data.