FIX: FetchMany(number of rows) ignores batch size with LOB columns (#346)

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> GitHub Issue: #345 

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### Summary   
Fixes FetchMany(number of rows) ignores batch size when table contains
an LOB


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---------

Co-authored-by: gargsaumya <saumyagarg.100@gmail.com>

Author: dlevy-msft-sql

mssql_python/pybind/ddbc_bindings.cpp

@@ -4033,13 +4033,15 @@ SQLRETURN FetchMany_wrap(SqlHandlePtr StatementHandle, py::list& rows, int fetch
             lobColumns.push_back(i + 1);  // 1-based
         }
     }
-
+    
+    // Initialized to 0 for LOB path counter; overwritten by ODBC in non-LOB path; 
+    SQLULEN numRowsFetched = 0;
     // If we have LOBs → fall back to row-by-row fetch + SQLGetData_wrap
     if (!lobColumns.empty()) {
         LOG("FetchMany_wrap: LOB columns detected (%zu columns), using per-row "
             "SQLGetData path",
             lobColumns.size());
-        while (true) {
+        while (numRowsFetched < (SQLULEN)fetchSize) {
             ret = SQLFetch_ptr(hStmt);
             if (ret == SQL_NO_DATA)
                 break;
@@ -4050,6 +4052,7 @@ SQLRETURN FetchMany_wrap(SqlHandlePtr StatementHandle, py::list& rows, int fetch
             SQLGetData_wrap(StatementHandle, numCols, row, charEncoding,
                             wcharEncoding);  // <-- streams LOBs correctly
             rows.append(row);
+            numRowsFetched++;
         }
         return SQL_SUCCESS;
     }
@@ -4063,8 +4066,7 @@ SQLRETURN FetchMany_wrap(SqlHandlePtr StatementHandle, py::list& rows, int fetch
         LOG("FetchMany_wrap: Error when binding columns - SQLRETURN=%d", ret);
         return ret;
     }
-
-    SQLULEN numRowsFetched;
+    
     SQLSetStmtAttr_ptr(hStmt, SQL_ATTR_ROW_ARRAY_SIZE, (SQLPOINTER)(intptr_t)fetchSize, 0);
     SQLSetStmtAttr_ptr(hStmt, SQL_ATTR_ROWS_FETCHED_PTR, &numRowsFetched, 0);