[FIX] PreparedStatement.executeBatch() When the Insert Sql Column Name Case Mismatch, Throws SQLServerException "Unable to retrieve column metadata."

src/main/java/com/microsoft/sqlserver/jdbc/SQLServerPreparedStatement.java

@@ -2210,7 +2210,14 @@ public int[] executeBatch() throws SQLServerException, BatchUpdateException, SQL
                                 jdbctype = ti.getSSType().getJDBCType().getIntValue();
                             }
                             if (null != bcOperationColumnList && !bcOperationColumnList.isEmpty()) {
-                                int columnIndex = bcOperationColumnList.indexOf(c.getColumnName());
+                                // find index ignore case
+                                int columnIndex = -1;
+                                for (int opi = 0; opi < bcOperationColumnList.size(); opi++) {
+                                    if (bcOperationColumnList.get(opi).equalsIgnoreCase(c.getColumnName())) {
+                                        columnIndex = opi;
+                                    }
+                                }
+
                                 if (columnIndex > -1) {
                                     columnMappings.put(columnIndex + 1, i);
                                     batchRecord.addColumnMetadata(columnIndex + 1, c.getColumnName(), jdbctype,

src/test/java/com/microsoft/sqlserver/jdbc/unit/statement/BatchExecutionTest.java

@@ -72,6 +72,8 @@ public class BatchExecutionTest extends AbstractTest {
             .escapeIdentifier(RandomUtil.getIdentifier("timestamptable1"));
     private static String timestampTable2 = AbstractSQLGenerator
             .escapeIdentifier(RandomUtil.getIdentifier("timestamptable2"));
+    private static String caseSensitiveTable = AbstractSQLGenerator
+            .escapeIdentifier(RandomUtil.getIdentifier("caseSensitiveTable"));
 
     /**
      * This tests the updateCount when the error query does cause a SQL state HY008.
@@ -568,6 +570,27 @@ public void testBatchStatementCancellation() throws Exception {
         }
     }
 
+    @Test
+    public void testExecuteBatchColumnCaseMismatch() throws Exception {
+        // Insert Timestamp using prepared statement when useBulkCopyForBatchInsert=true
+        try (Connection con = DriverManager.getConnection(connectionString
+                + ";useBulkCopyForBatchInsert=true;sendTemporalDataTypesAsStringForBulkCopy=false;")) {
+            try (Statement statement = con.createStatement()) {
+                TestUtils.dropTableIfExists(caseSensitiveTable, statement);
+                String createSql = "CREATE TABLE" + caseSensitiveTable + " (c1 varchar(10))";
+                statement.execute(createSql);
+            }
+            // upper case C1
+            try (PreparedStatement preparedStatement = con.prepareStatement("INSERT INTO " + caseSensitiveTable + "(C1) VALUES(?)")) {
+                preparedStatement.setObject(1, "value1");
+                preparedStatement.addBatch();
+                preparedStatement.setObject(1, "value2");
+                preparedStatement.addBatch();
+                preparedStatement.executeBatch();
+            }
+        }
+    }
+
     /**
      * Get a PreparedStatement object and call the addBatch() method with 3 SQL statements and call the executeBatch()
      * method and it should return array of Integer values of length 3
@@ -839,6 +862,7 @@ private static void dropTable() throws SQLException {
             TestUtils.dropTableIfExists(AbstractSQLGenerator.escapeIdentifier(ctstable4), stmt);
             TestUtils.dropTableIfExists(timestampTable1, stmt);
             TestUtils.dropTableIfExists(timestampTable2, stmt);
+            TestUtils.dropTableIfExists(caseSensitiveTable, stmt);
         }
     }