FIX: Stored datetime.time values have the microseconds attribute set to zero

[jahnvi480]

Work Item / Issue Reference

AB#38820

GitHub Issue: #203

---

Summary

This pull request introduces significant improvements to how SQL TIME/TIME2 values are handled in the MSSQL Python driver, transitioning from native C-type bindings to text-based representations. The changes ensure correct parsing, binding, and conversion between SQL TIME values and Python datetime.time objects, addressing edge cases and improving compatibility.

SQL TIME/TIME2 Handling Improvements

• Changed TIME/TIME2 parameter binding in mssql_python/cursor.py to use SQL_TYPE_TIME and text C-types (SQL_C_CHAR), and normalized Python datetime.time values to ISO text format with microseconds.
• Updated C++ bindings in ddbc_bindings.cpp to bind and fetch TIME/TIME2 columns as text buffers instead of native structs, and introduced a robust parser (ParseSqlTimeTextToPythonObject) for converting SQL time text to Python objects.
• Adjusted row size calculations and buffer allocations for TIME/TIME2 columns to use the new maximum text length constant (SQL_TIME_TEXT_MAX_LEN).

Testing and Utilities

• Exposed the time-text parser as a test helper in the Python module, allowing for unit testing of TIME/TIME2 parsing edge cases.

Miscellaneous

• Improved table cleanup in tests by switching to drop_table_if_exists for reliability.

[Copilot]

Pull request overview

This PR fixes microsecond loss when round-tripping SQL Server TIME/TIME2 values by switching Python datetime.time binding to a text C-type with microsecond precision and updating the C++ fetch/batch-fetch paths to parse TIME2 from text back into datetime.time.

Changes:

• Bind Python datetime.time parameters as text (SQL_C_CHAR/SQL_C_WCHAR) using isoformat(timespec="microseconds").
• Fetch SQL_SS_TIME2 as text in both SQLGetData_wrap and batch fetch, converting to datetime.time via a new parser.
• Add a regression test asserting TIME(6) preserves microseconds on insert/select.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
tests/test_004_cursor.py	Adds a regression test for TIME microsecond round-trip; minor formatting updates to SQL strings.
mssql_python/pybind/ddbc_bindings.cpp	Adds a TIME text parser and changes SQL_SS_TIME2 retrieval/binding to use SQL_C_CHAR buffers.
mssql_python/cursor.py	Changes TIME parameter mapping and normalizes TIME values to microsecond ISO text in execute/executemany binding.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[github-actions]

📊 Code Coverage Report

🔥 Diff Coverage 98%

🎯 Overall Coverage 77%

📈 Total Lines Covered: 5734 out of 7395 📁 Project: mssql-python

---

Diff Coverage

Diff: main...HEAD, staged and unstaged changes

• mssql_python/cursor.py (100%)
• mssql_python/pybind/ddbc_bindings.cpp (98.8%): Missing lines 3335

Summary

• Total: 91 lines
• Missing: 1 line
• Coverage: 98%

mssql_python/pybind/ddbc_bindings.cpp

Lines 3331-3339

  3331                     } else {
  3332                         row.append(ParseSqlTimeTextToPythonObject(timeTextBuffer, timeDataLen));
  3333                     }
  3334                 } else {
! 3335                     LOG("SQLGetData: Error retrieving SQL_SS_TIME2 for column "
  3336                         "%d - SQLRETURN=%d",
  3337                         i, ret);
  3338                     row.append(py::none());
  3339                 }

---

---

📋 Files Needing Attention

📉 Files with overall lowest coverage (click to expand)

mssql_python.pybind.logger_bridge.hpp: 58.8%
mssql_python.pybind.logger_bridge.cpp: 59.2%
mssql_python.pybind.ddbc_bindings.h: 67.8%
mssql_python.pybind.ddbc_bindings.cpp: 70.4%
mssql_python.row.py: 70.5%
mssql_python.pybind.connection.connection.cpp: 75.3%
mssql_python.__init__.py: 77.1%
mssql_python.ddbc_bindings.py: 79.6%
mssql_python.pybind.connection.connection_pool.cpp: 79.6%
mssql_python.connection.py: 85.2%

---

🔗 Quick Links

⚙️ Build Summary	📋 Coverage Details
View Azure DevOps Build	Browse Full Coverage Report