Excel-VBA-Libraries

SQL for Excel via ADODB — query Excel sheets as database tables using ACE.OLEDB or Jet.OLEDB providers. Use when writing SQL against Excel workbooks, debugging ADODB connection strings, building SELECT/JOIN/GROUP BY queries on sheet data, working with SqlUtils macros (SqlQuery, SqlJoin, SqlGroupBy, SqlRangeQuery), or troubleshooting Excel-as-database issues (type inference, header scanning, IMEX mode, max rows).

Excel VBA Libraries development best practices and patterns. Use when writing, reviewing, or refactoring VBA code for Excel, especially for .xlam add-ins, .bas modules, worksheet functions, array/matrix/statistical algorithms, string/date processing, RegExp, file I/O, SQL/JSON, or dictionary/set structures. Also use for debugging type-safety, performance optimization, and ensuring cross-version Excel compatibility (32/64-bit, legacy vs dynamic arrays).

Python development for Excel COM automation, numpy/scipy cross-validation, and test infrastructure. Use when writing pywin32 Excel automation scripts, numpy/scipy statistical validation, openpyxl data handling, or Python-VBA cross-validation tests. Covers COM threading safety, SafeArray marshaling, datetime timezone handling, and Python-VBA type bridging.