Simplify options for disable_projection_and_casing

Since `auto` is mostly the same as `false`, we can limit the options to just `auto` and `always`.
awslabs · Jul 29, 2022 · 6ed5bb1 · 6ed5bb1
1 parent 235cd33
commit 6ed5bb1
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Showing 2 changed files with 9 additions and 13 deletions.
diff --git a/athena-dynamodb/README.md b/athena-dynamodb/README.md
@@ -98,17 +98,12 @@ If glue is disabled, we perform schema inference. Under schema inference, we eva
     - This disables projection and casing when we see a previously unsupported type
       and we see that the user does not have column name mapping on their table.
     - This is the default setting.
-- true
+- always
     - This disables projection and casing unconditionally.
       This is useful when users have casing in their ddb column names but do not want to
       specify a column name mapping at all.
-- false
-    - This enables projection and casing unconditionally.
-      This is useful when the users want projection enabled (mainly for bandwidth and latency)
-      and are not worried about their columns with casing or already have a column name mapping
-      for those columns.
 
-Caveats with setting this to true or auto:
+Caveats with this new feature:
 
 - May incur higher bandwidth usage depending on your query.
 This not a problem if your lambda is in the same region as your ddb table.

diff --git a/...ynamodb/src/main/java/com/amazonaws/athena/connectors/dynamodb/DynamoDBRecordHandler.java b/...ynamodb/src/main/java/com/amazonaws/athena/connectors/dynamodb/DynamoDBRecordHandler.java
@@ -142,7 +142,13 @@ protected void readWithConstraint(BlockSpiller spiller, ReadRecordsRequest recor
         logger.info(DISABLE_PROJECTION_AND_CASING_ENV + " environment variable set to: " + disableProjectionAndCasingEnvValue);
 
         boolean disableProjectionAndCasing = false;
-        if (disableProjectionAndCasingEnvValue.equals("auto")) {
+        if (disableProjectionAndCasingEnvValue.equals("always")) {
+            // This is when the user wants to turn this on unconditionally to
+            // solve their casing issues even when they do not have `set` or
+            // `decimal` columns.
+            disableProjectionAndCasing = true;
+        }
+        else { // *** We default to auto when the variable is not set ***
             // In the automatic case, we will try to mimic the behavior prior to the support of `set` and `decimal` types as much
             // as possible.
             //
@@ -165,11 +171,6 @@ protected void readWithConstraint(BlockSpiller spiller, ReadRecordsRequest recor
             logger.info("ColumnNameMapping isEmpty: " + recordMetadata.getColumnNameMapping().isEmpty());
             logger.info("Resolving disableProjectionAndCasing to: " + disableProjectionAndCasing);
         }
-        else {
-            // We also support the user turning this on unconditionally to solve their casing issues even when they do not have `set` or `decimal`
-            // columns.
-            disableProjectionAndCasing = disableProjectionAndCasingEnvValue.equals("true");
-        }
 
         Iterator<Map<String, AttributeValue>> itemIterator = getIterator(split, tableName, recordsRequest.getSchema(), disableProjectionAndCasing);
         DynamoDBFieldResolver resolver = new DynamoDBFieldResolver(recordMetadata);