Add support for case sensitive identifiers

presto-main/src/main/java/io/prestosql/metadata/Metadata.java

@@ -485,4 +485,6 @@ default ResolvedFunction getCoercion(Type fromType, Type toType)
     ColumnPropertyManager getColumnPropertyManager();
 
     AnalyzePropertyManager getAnalyzePropertyManager();
+
+    NameCanonicalizer getNameCanonicalizer(Session session, String catalogName);
 }

presto-main/src/main/java/io/prestosql/metadata/MetadataManager.java

@@ -118,6 +118,7 @@
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
 import static io.prestosql.metadata.FunctionId.toFunctionId;
 import static io.prestosql.metadata.FunctionKind.AGGREGATE;
+import static io.prestosql.metadata.NameCanonicalizer.LEGACY_NAME_CANONICALIZER;
 import static io.prestosql.metadata.QualifiedObjectName.convertFromSchemaTableName;
 import static io.prestosql.metadata.Signature.mangleOperatorName;
 import static io.prestosql.spi.StandardErrorCode.FUNCTION_IMPLEMENTATION_MISSING;
@@ -1510,6 +1511,16 @@ public AnalyzePropertyManager getAnalyzePropertyManager()
         return analyzePropertyManager;
     }
 
+    @Override
+    public NameCanonicalizer getNameCanonicalizer(Session session, String catalogName)
+    {
+        Optional<CatalogMetadata> metadata = getOptionalCatalogMetadata(session, catalogName);
+        if (metadata.isPresent()) {
+            return (identifier, delimited) -> metadata.get().getMetadata().canonicalize(session.toConnectorSession(metadata.get().getCatalogName()), identifier, delimited);
+        }
+        return LEGACY_NAME_CANONICALIZER;
+    }
+
     //
     // Helpers
     //

presto-main/src/main/java/io/prestosql/metadata/NameCanonicalizer.java

@@ -0,0 +1,28 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.prestosql.metadata;
+
+import static java.util.Locale.ENGLISH;
+
+public interface NameCanonicalizer
+{
+    NameCanonicalizer LEGACY_NAME_CANONICALIZER = (identifier, delimited) -> identifier.toLowerCase(ENGLISH);
+
+    String canonicalize(String identifier, boolean delimited);
+
+    default String canonicalize(NamePart namePart)
+    {
+        return canonicalize(namePart.getValue(), namePart.isDelimited());
+    }
+}

presto-main/src/test/java/io/prestosql/metadata/AbstractMockMetadata.java

@@ -64,6 +64,7 @@
 
 import static io.prestosql.metadata.FunctionId.toFunctionId;
 import static io.prestosql.metadata.FunctionKind.SCALAR;
+import static io.prestosql.metadata.NameCanonicalizer.LEGACY_NAME_CANONICALIZER;
 import static io.prestosql.spi.StandardErrorCode.FUNCTION_NOT_FOUND;
 import static io.prestosql.spi.type.DoubleType.DOUBLE;
 
@@ -692,4 +693,10 @@ public Optional<ProjectionApplicationResult<TableHandle>> applyProjection(Sessio
     {
         return Optional.empty();
     }
+
+    @Override
+    public NameCanonicalizer getNameCanonicalizer(Session session, String catalogName)
+    {
+        return LEGACY_NAME_CANONICALIZER;
+    }
 }

presto-plugin-toolkit/src/main/java/io/prestosql/plugin/base/classloader/ClassLoaderSafeConnectorMetadata.java

@@ -661,4 +661,12 @@ public Optional<ConnectorTableHandle> applySample(ConnectorSession session, Conn
             return delegate.applySample(session, table, sampleType, sampleRatio);
         }
     }
+
+    @Override
+    public String canonicalize(ConnectorSession session, String identifier, boolean delimited)
+    {
+        try (ThreadContextClassLoader ignored = new ThreadContextClassLoader(classLoader)) {
+            return delegate.canonicalize(session, identifier, delimited);
+        }
+    }
 }

presto-spi/src/main/java/io/prestosql/spi/connector/ConnectorMetadata.java

@@ -41,6 +41,7 @@
 import static java.lang.String.format;
 import static java.util.Collections.emptyList;
 import static java.util.Collections.emptyMap;
+import static java.util.Locale.ENGLISH;
 import static java.util.stream.Collectors.toList;
 
 public interface ConnectorMetadata
@@ -806,4 +807,14 @@ default Optional<ConnectorTableHandle> applySample(ConnectorSession session, Con
     {
         return Optional.empty();
     }
+
+    /**
+     * Canonicalizes the provided SQL identifier according to connector-specific rules
+     * for the purpose of providing the name in metadata APIs
+     */
+    default String canonicalize(ConnectorSession session, String identifier, boolean delimited)
+    {
+        // TODO: Move to model which is in accordance with SQL specification
+        return identifier.toLowerCase(ENGLISH);
+    }
 }