Additonal PR reviews

microsoft · Jul 5, 2024 · e625a69 · e625a69
1 parent 6b49454
commit e625a69
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Showing 2 changed files with 14 additions and 3 deletions.
diff --git a/src/main/java/com/microsoft/sqlserver/jdbc/SQLServerBulkCopy.java b/src/main/java/com/microsoft/sqlserver/jdbc/SQLServerBulkCopy.java
@@ -1740,14 +1740,24 @@ private void getDestinationMetadata() throws SQLServerException {
         }
 
         if (null == destColumnMetadata || destColumnMetadata.isEmpty()) {
-
             if (connection.getEnableBulkCopyCache()) {
                 DESTINATION_COL_METADATA_LOCK.lock();
                 destColumnMetadata = BULK_COPY_OPERATION_CACHE.get(key);
 
                 if (null == destColumnMetadata || destColumnMetadata.isEmpty()) {
                     try {
                         setDestinationColumnMetadata(escapedDestinationTableName);
+
+                        // We are caching the following metadata about the table:
+                        // 1. collation_name
+                        // 2. is_computed
+                        // 3. encryption_type
+                        //
+                        // Using this caching method, 'enableBulkCopyCache', may have unintended consequences if the
+                        // table changes somehow between inserts. For example, if the collation_name changes, the
+                        // driver will not be aware of this and the inserted data will likely be corrupted. In such
+                        // scenario, we can't detect this without making an additional metadata query, which would
+                        // defeat the purpose of caching.
                         BULK_COPY_OPERATION_CACHE.put(key, destColumnMetadata);
                     } finally {
                         DESTINATION_COL_METADATA_LOCK.unlock();

diff --git a/src/test/java/com/microsoft/sqlserver/jdbc/unit/statement/BatchExecutionTest.java b/src/test/java/com/microsoft/sqlserver/jdbc/unit/statement/BatchExecutionTest.java
@@ -161,8 +161,9 @@ public void testSqlServerBulkCopyCachingConnectionLevel() throws Exception {
             stmt.execute(createSqlTable1);
             stmt.execute(createSqlTable2);
 
-            // Calling getSuperClass() because SQLServerConnection is the parent
-            Field bulkcopyMetadataCacheField = con.getClass().getSuperclass().getDeclaredField("BULK_COPY_OPERATION_CACHE");
+            Field bulkcopyMetadataCacheField = TestUtils.getJVMVersion() > 8 ?
+                    con.getClass().getSuperclass().getDeclaredField("BULK_COPY_OPERATION_CACHE") :
+                    con.getClass().getDeclaredField("BULK_COPY_OPERATION_CACHE");
             bulkcopyMetadataCacheField.setAccessible(true);
             Object bulkcopyCache = bulkcopyMetadataCacheField.get(con);