From ee473c0cff403400bbd072d152b18461ac03de5c Mon Sep 17 00:00:00 2001
From: praveenkrishna <praveenkrishna@tutanota.com>
Date: Thu, 22 Jun 2023 11:55:53 +0530
Subject: [PATCH] Derive read column type from the TypeCoercer

---
 .../java/io/trino/plugin/hive/HivePageSourceProvider.java  | 5 +++--
 .../java/io/trino/plugin/hive/coercions/CoercionUtils.java | 7 +++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/plugin/trino-hive/src/main/java/io/trino/plugin/hive/HivePageSourceProvider.java b/plugin/trino-hive/src/main/java/io/trino/plugin/hive/HivePageSourceProvider.java
index 14c80878e579..4cc269ce57b8 100644
--- a/plugin/trino-hive/src/main/java/io/trino/plugin/hive/HivePageSourceProvider.java
+++ b/plugin/trino-hive/src/main/java/io/trino/plugin/hive/HivePageSourceProvider.java
@@ -71,6 +71,7 @@
 import static io.trino.plugin.hive.HivePageSourceProvider.ColumnMapping.toColumnHandles;
 import static io.trino.plugin.hive.HivePageSourceProvider.ColumnMappingKind.PREFILLED;
 import static io.trino.plugin.hive.HiveSessionProperties.getTimestampPrecision;
+import static io.trino.plugin.hive.coercions.CoercionUtils.createTypeFromCoercer;
 import static io.trino.plugin.hive.util.HiveBucketing.HiveBucketFilter;
 import static io.trino.plugin.hive.util.HiveBucketing.getHiveBucketFilter;
 import static io.trino.plugin.hive.util.HiveUtil.getPrefilledColumnValue;
@@ -564,14 +565,14 @@ public static List<HiveColumnHandle> toColumnHandles(List<ColumnMapping> regular
                                     projectedColumn.getDereferenceIndices(),
                                     projectedColumn.getDereferenceNames(),
                                     fromHiveType,
-                                    fromHiveType.getType(typeManager, timestampPrecision));
+                                    createTypeFromCoercer(typeManager, fromHiveType, columnHandle.getHiveType(), timestampPrecision));
                         });
 
                         return new HiveColumnHandle(
                                 columnHandle.getBaseColumnName(),
                                 columnHandle.getBaseHiveColumnIndex(),
                                 fromHiveTypeBase,
-                                fromHiveTypeBase.getType(typeManager, timestampPrecision),
+                                createTypeFromCoercer(typeManager, fromHiveTypeBase, columnHandle.getBaseHiveType(), timestampPrecision),
                                 newColumnProjectionInfo,
                                 columnHandle.getColumnType(),
                                 columnHandle.getComment());
diff --git a/plugin/trino-hive/src/main/java/io/trino/plugin/hive/coercions/CoercionUtils.java b/plugin/trino-hive/src/main/java/io/trino/plugin/hive/coercions/CoercionUtils.java
index a77641c1d780..abbe99be9b4e 100644
--- a/plugin/trino-hive/src/main/java/io/trino/plugin/hive/coercions/CoercionUtils.java
+++ b/plugin/trino-hive/src/main/java/io/trino/plugin/hive/coercions/CoercionUtils.java
@@ -68,6 +68,13 @@ public final class CoercionUtils
 {
     private CoercionUtils() {}
 
+    public static Type createTypeFromCoercer(TypeManager typeManager, HiveType fromHiveType, HiveType toHiveType, HiveTimestampPrecision timestampPrecision)
+    {
+        return createCoercer(typeManager, fromHiveType, toHiveType, timestampPrecision)
+                .map(TypeCoercer::getFromType)
+                .orElseGet(() -> fromHiveType.getType(typeManager, timestampPrecision));
+    }
+
     public static Optional<TypeCoercer<? extends Type, ? extends Type>> createCoercer(TypeManager typeManager, HiveType fromHiveType, HiveType toHiveType, HiveTimestampPrecision timestampPrecision)
     {
         if (fromHiveType.equals(toHiveType)) {