Connect-DbaInstance - Return the connection of a server object after reading its current database

[andreasjordan]

Summary

Connect-DbaInstance -SqlInstance <server object> -Database X has to know which database the connection of that object is on, and a server object that was connected without -Database has an empty CurrentDatabase until its connection is opened once. The command opened it with an explicit ConnectionContext.Connect() and left it open.

That connection never went back to the pool: SMO returns a pooled connection after each batch only when it opened the connection itself, an explicit Connect() keeps it checked out until Disconnect(). So every server object that went through this path kept one session for the life of the process, which only a Disconnect-DbaInstance on that very object could release. ClearAllPools does not touch a checked-out connection either.

The visible consequence, found during the parallel full runs of 2026-09-19/20: a loop that hands fresh server objects to Invoke-DbaQuery -SqlInstance $server -Database X exhausts the 100-connection pool after 100 iterations and every later connect fails with "Timeout expired ... obtaining a connection from the pool". The test harness hit that after ~100 test files because its environment check does exactly this once per file.

The fix reads the value and returns the connection right away, unless the caller had opened it before, in which case it stays theirs. SMO reconnects on the next batch as it always did. The value is kept in a variable, because Disconnect() clears CurrentDatabase again.

The clone path itself (Copy, DatabaseName, the connection string variants) was checked step by step on the lab and is clean; the only session that stayed behind was the one of the object passed in.

Measurement

Sessions of the calling process on the instance, counted after ClearAllPools so that only checked-out connections and the counting session itself remain (pwsh, SQL Server 2019):

Step	Sessions
baseline	1
$server = Connect-DbaInstance (no -Database)	1
Invoke-DbaQuery -SqlInstance $server -Database master -Query "SELECT 1"	2, $server.ConnectionContext.SqlConnectionObject.State = Open
$server.ConnectionContext.Disconnect()	1
server connected with -Database master, then the same query	1

Windows PowerShell 5.1 behaves the same.

Test plan

• New Context in Connect-DbaInstance.Tests.ps1: three server objects with distinct client names go through Connect-DbaInstance -Database master (same database, no clone) and through Invoke-DbaQuery -Database tempdb (clone), the session count after Clear-DbaConnectionPool must not grow.
• Red on old: both new tests fail on development ("Expected 2, but got 5" and "Expected 2, but got 8"), the rest of the file passes.
• Whole file green on the lab with the fix, PowerShell 7 and Windows PowerShell 5.1 alike: 59 tests, 57 passed, 2 skipped (Azure SQL Database).

created by Claude and reviewed by Andreas Jordan

🤖 Generated with Claude Code

[potatoqualitee]

Reviewed the complete connection-lifecycle patch at this exact head, including SMO ownership semantics, pooled/multi-input/error cleanup paths, regression coverage, discussions, and the passing exact-head MULTI CI lane. No material defects found.

[potatoqualitee]

going to get chatgpt pro on this, brb

[potatoqualitee]

awesome, pro approves 👏🏼