[#2117] improvement(api): Type adds UNKNOWN column data type to handl…

…e an unresolvable type from the catalog

api/src/main/java/com/datastrato/gravitino/rel/types/Type.java

@@ -73,7 +73,10 @@ enum Name {
     UNION,
 
     /** The null type. A null type represents a value that is null. */
-    NULL
+    NULL,
+
+    /** The unknown type. An unknown type represents an unresolvable type. */
+    UNKNOWN
   }
 
   /** The base type of all primitive types. */

api/src/main/java/com/datastrato/gravitino/rel/types/Types.java

@@ -34,6 +34,28 @@ public String simpleString() {
     }
   }
 
+  /** The data type representing `UNKNOWN` values. */
+  public static class UnknownType implements Type {
+    private static final UnknownType INSTANCE = new UnknownType();
+
+    /** @return The singleton instance of {@link UnknownType}. */
+    public static UnknownType get() {
+      return INSTANCE;
+    }
+
+    private UnknownType() {}
+
+    @Override
+    public Name name() {
+      return Name.UNKNOWN;
+    }
+
+    @Override
+    public String simpleString() {
+      return "unknown";
+    }
+  }
+
   /** The boolean type in Gravitino. */
   public static class BooleanType extends Type.PrimitiveType {
     private static final BooleanType INSTANCE = new BooleanType();

api/src/test/java/com/datastrato/gravitino/rel/TestTypes.java

@@ -24,6 +24,11 @@ public void testPrimitiveTypes() {
     Assertions.assertSame(nullType, Types.NullType.get());
     Assertions.assertEquals("null", nullType.simpleString());
 
+    Types.UnknownType unknownType = Types.UnknownType.get();
+    Assertions.assertEquals(Type.Name.UNKNOWN, unknownType.name());
+    Assertions.assertSame(unknownType, Types.UnknownType.get());
+    Assertions.assertEquals("unknown", unknownType.simpleString());
+
     Types.ByteType byteType = Types.ByteType.get();
     Assertions.assertEquals(Type.Name.BYTE, byteType.name());
     Assertions.assertSame(byteType, Types.ByteType.get());

catalogs/catalog-hive/src/main/java/com/datastrato/gravitino/catalog/hive/converter/FromHiveType.java

@@ -54,7 +54,7 @@ public static Type convert(String hiveType) throws IllegalArgumentException {
    * @return The equivalent Gravitino Type.
    * @throws IllegalArgumentException if the Hive data type category is unknown or unsupported.
    */
-  private static Type toGravitinoType(TypeInfo hiveTypeInfo) throws IllegalArgumentException {
+  public static Type toGravitinoType(TypeInfo hiveTypeInfo) throws IllegalArgumentException {
     switch (hiveTypeInfo.getCategory()) {
       case PRIMITIVE:
         switch (hiveTypeInfo.getTypeName()) {
@@ -98,8 +98,7 @@ private static Type toGravitinoType(TypeInfo hiveTypeInfo) throws IllegalArgumen
               return Types.DecimalType.of(decimalTypeInfo.precision(), decimalTypeInfo.scale());
             }
 
-            throw new IllegalArgumentException(
-                "Unknown Hive type: " + hiveTypeInfo.getQualifiedName());
+            return Types.UnknownType.get();
         }
       case LIST:
         return Types.ListType.nullable(
@@ -128,8 +127,7 @@ private static Type toGravitinoType(TypeInfo hiveTypeInfo) throws IllegalArgumen
                 .map(FromHiveType::toGravitinoType)
                 .toArray(Type[]::new));
       default:
-        throw new IllegalArgumentException(
-            "Unknown category of Hive type: " + hiveTypeInfo.getCategory());
+        return Types.UnknownType.get();
     }
   }
 

catalogs/catalog-hive/src/test/java/com/datastrato/gravitino/catalog/converter/TestTypeConverter.java

@@ -29,7 +29,9 @@
 
 import com.datastrato.gravitino.catalog.hive.converter.FromHiveType;
 import com.datastrato.gravitino.catalog.hive.converter.ToHiveType;
+import com.datastrato.gravitino.rel.types.Types;
 import java.util.Arrays;
+import org.apache.hadoop.hive.serde2.typeinfo.PrimitiveTypeInfo;
 import org.apache.hadoop.hive.serde2.typeinfo.TypeInfo;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
@@ -69,11 +71,20 @@ public void testTypeConverter() {
                 Arrays.asList(
                     getPrimitiveTypeInfo(STRING_TYPE_NAME), getPrimitiveTypeInfo(INT_TYPE_NAME)))
             .getTypeName());
+    Assertions.assertEquals(
+        Types.UnknownType.get(), FromHiveType.toGravitinoType(new UnknownTypeInfo()));
   }
 
   private void testConverter(String typeName) {
     TypeInfo hiveType = getTypeInfoFromTypeString(typeName);
     TypeInfo convertedType = ToHiveType.convert(FromHiveType.convert(hiveType.getTypeName()));
     Assertions.assertEquals(hiveType, convertedType);
   }
+
+  static class UnknownTypeInfo extends PrimitiveTypeInfo {
+    @Override
+    public String getTypeName() {
+      return Types.UnknownType.get().simpleString();
+    }
+  }
 }

catalogs/catalog-jdbc-mysql/src/main/java/com/datastrato/gravitino/catalog/mysql/converter/MysqlTypeConverter.java

@@ -55,7 +55,7 @@ public Type toGravitinoType(JdbcTypeBean typeBean) {
       case BINARY:
         return Types.BinaryType.get();
       default:
-        throw new IllegalArgumentException("Not a supported type: " + typeBean.getTypeName());
+        return Types.UnknownType.get();
     }
   }
 

catalogs/catalog-jdbc-mysql/src/test/java/com/datastrato/gravitino/catalog/mysql/converter/TestMysqlTypeConverter.java

@@ -44,6 +44,8 @@ public void testToGravitinoType() {
     checkJdbcTypeToGravitinoType(Types.FixedCharType.of(20), CHAR, "20", null);
     checkJdbcTypeToGravitinoType(Types.StringType.get(), TEXT, null, null);
     checkJdbcTypeToGravitinoType(Types.BinaryType.get(), BINARY, null, null);
+    checkJdbcTypeToGravitinoType(
+        Types.UnknownType.get(), Types.UnknownType.get().simpleString(), null, null);
   }
 
   @Test

catalogs/catalog-jdbc-postgresql/src/main/java/com/datastrato/gravitino/catalog/postgresql/converter/PostgreSqlTypeConverter.java

@@ -59,7 +59,7 @@ public Type toGravitinoType(JdbcTypeBean typeBean) {
       case BYTEA:
         return Types.BinaryType.get();
       default:
-        throw new IllegalArgumentException("Not a supported type: " + typeBean);
+        return Types.UnknownType.get();
     }
   }
 

catalogs/catalog-jdbc-postgresql/src/test/java/com/datastrato/gravitino/catalog/postgresql/converter/TestPostgreSqlTypeConverter.java

@@ -47,6 +47,8 @@ public void testToGravitinoType() {
     checkJdbcTypeToGravitinoType(Types.FixedCharType.of(20), BPCHAR, "20", null);
     checkJdbcTypeToGravitinoType(Types.StringType.get(), TEXT, null, null);
     checkJdbcTypeToGravitinoType(Types.BinaryType.get(), BYTEA, null, null);
+    checkJdbcTypeToGravitinoType(
+        Types.UnknownType.get(), Types.UnknownType.get().simpleString(), null, null);
   }
 
   @Test