Add ODBC connection pooling design plan (ADO #47317) - #293
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Saurabh Singh (saurabh500) wants to merge 1 commit into
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Add ODBC connection pooling design plan (ADO #47317)#293Saurabh Singh (saurabh500) wants to merge 1 commit into
Saurabh Singh (saurabh500) wants to merge 1 commit into
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Design plan for enabling connection pool constructs in mssql-odbc so mssql-python's client-side pool can safely reuse a physical Rust ODBC connection. Covers reset/liveness/isolation semantics, msodbcsql cross-reference, and a 4-stage implementation breakdown. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 63e24621-7665-4572-a5b8-e5dfa55060a0
This was referenced Aug 14, 2026
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Summary
Base PR for the mssql-odbc connection pooling effort (ADO #47317). Adds the design plan at
docs/odbc-connection-pooling-plan.md.The plan enables
mssql-python's existing client-side pool to safely reuse a physical Rust ODBC connection — no second pool in Rust; we supply only the ODBC/TDS reset, liveness, transaction, and isolation semantics that make reuse safe.Key findings captured in the doc
msodbcsqlC++ driver (discoveries D1–D9).sp_reset_connectiondoes not reset the transaction isolation level (a SQL Server limitation).mssql-pythonworks around this in PR #343 by re-applyingSET TRANSACTION ISOLATION LEVEL READ COMMITTEDon every checkout — ourSQL_ATTR_TXN_ISOLATIONhandler must honor this and carry the armed reset bit.Implementation stages (tracked as ADO child Tasks of #47317)
SQL_ATTR_CONNECTION_DEAD+SQL_ATTR_RESET_CONNECTION) — [AB#47338]Each stage will land as its own PR stacked on top of this base.
Notes