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Author: KodaiD

core/src/main/java/com/scalar/db/common/CoreError.java

@@ -796,10 +796,16 @@ public enum CoreError implements ScalarDbError {
       "SQLite does not support the altering column type feature",
       "",
       ""),
-  JDBC_UNSUPPORTED_COLUMN_TYPE_CONVERSION(
+  JDBC_ORACLE_UNSUPPORTED_COLUMN_TYPE_CONVERSION(
       Category.USER_ERROR,
       "0239",
-      "The storage does not support column type conversion from %s to %s",
+      "Oracle does not support column type conversion from %s to %s",
+      "",
+      ""),
+  JDBC_DB2_UNSUPPORTED_COLUMN_TYPE_CONVERSION(
+      Category.USER_ERROR,
+      "0240",
+      "Db2 does not support column type conversion from %s to %s",
       "",
       ""),
 

core/src/main/java/com/scalar/db/storage/jdbc/RdbEngineDb2.java

@@ -553,7 +553,7 @@ public void throwIfRenameColumnNotSupported(String columnName, TableMetadata tab
   public void throwIfAlterColumnTypeNotSupported(DataType from, DataType to) {
     if (from == DataType.BLOB && to == DataType.TEXT) {
       throw new UnsupportedOperationException(
-          CoreError.JDBC_UNSUPPORTED_COLUMN_TYPE_CONVERSION.buildMessage(
+          CoreError.JDBC_DB2_UNSUPPORTED_COLUMN_TYPE_CONVERSION.buildMessage(
               from.toString(), to.toString()));
     }
   }

core/src/main/java/com/scalar/db/storage/jdbc/RdbEngineOracle.java

@@ -447,7 +447,7 @@ public String tryAddIfNotExistsToCreateIndexSql(String createIndexSql) {
   public void throwIfAlterColumnTypeNotSupported(DataType from, DataType to) {
     if (!(from == DataType.INT && to == DataType.BIGINT)) {
       throw new UnsupportedOperationException(
-          CoreError.JDBC_UNSUPPORTED_COLUMN_TYPE_CONVERSION.buildMessage(
+          CoreError.JDBC_ORACLE_UNSUPPORTED_COLUMN_TYPE_CONVERSION.buildMessage(
               from.toString(), to.toString()));
     }
   }