The previous coding did not correctly check for errors from the driver's
Next() or Close(), which could mask genuine errors from the database, as
witnessed in issue #6651.
Even after this change errors from Close() will be ignored if the query
returned no rows (as Rows.Next will have closed the handle already), but it
is a lot easier for the drivers to guard against that.
Fixes#6651.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/41590043
New test added in CL 14611045 causes a deadlock when
running the tests with -cpu=n,n because the fakedb
driver always waits when opening a new connection after
running TestConnectionLeak. Reset its state after.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/14780043
CL 10726044 introduced a race condition which causes connections
to be leaked under certain circumstances. If SetMaxOpenConns is
used, the application eventually deadlocks. Otherwise, the number
of open connections just keep growing indefinitely.
Fixes#6593
R=golang-dev, bradfitz, tad.glines, bketelsen
CC=golang-dev
https://golang.org/cl/14611045
Update #4805
Add the ability to set an open connection limit.
Fixed case where the Conn finalCloser was being called with db.mu locked.
Added separate benchmarks for each path for Exec and Query.
Replaced slice based idle pool with list based idle pool.
R=bradfitz
CC=golang-dev
https://golang.org/cl/10726044
Breaks build, and has a race.
««« original CL description
database/sql: add SetMaxOpenConns
Update #4805
Add the ability to set an open connection limit.
Fixed case where the Conn finalCloser was being called with db.mu locked.
Added seperate benchmarks for each path for Exec and Query.
Replaced slice based idle pool with list based idle pool.
R=bradfitz
CC=golang-dev
https://golang.org/cl/10726044
»»»
R=golang-dev
CC=golang-dev
https://golang.org/cl/13252046
Update #4805
Add the ability to set an open connection limit.
Fixed case where the Conn finalCloser was being called with db.mu locked.
Added seperate benchmarks for each path for Exec and Query.
Replaced slice based idle pool with list based idle pool.
R=bradfitz
CC=golang-dev
https://golang.org/cl/10726044
Rows.Close.
Previously, callers that followed the example code (but not call
rows.Close after "for rows.Next() { ... }") could leak statements if
the driver returned an error other than io.EOF.
R=bradfitz, alex.brainman
CC=golang-dev, rsc
https://golang.org/cl/12677050
The refcounting of driver Conns was completedly busted and
would leak (be held open forever) with any reasonable
load. This was a significant regression from Go 1.0.
The core of this patch is removing one line:
s.db.addDep(dc, s)
A database conn (dc) is a resource that be re-created any time
(but cached for speed) should not be held open forever with a
dependency refcount just because the Stmt (s) is alive (which
typically last for long periods of time, like forever).
The meat of the patch is new tests. In fixing the real issue,
a lot of tests then failed due to the fakedb_test.go's paranoia
about closing a fakeConn while it has open fakeStmts on it. I
could've ignored that, but that's been a problem in the past for
other bugs.
Instead, I now track per-Conn open statements and close them
when the the conn closes. The proper way to do this would've
been making *driverStmt a finalCloser and using the dep mechanism,
but it was much more invasive. Added a TODO instead.
I'd like to give a way for drivers to opt-out of caring about
driver.Stmt closes before a driver.Conn close, but that's a TODO
for the future, and that TODO is added in this CL.
I know this is very late for Go 1.1, but database/sql is
currently nearly useless without this.
I'd like to believe all these database/sql bugs in the past
release cycle are the result of increased usage, number of
drivers, and good feedback from increasingly-capable Go
developers, and not the result of me sucking. It's also hard
with all the real drivers being out-of-tree, so I'm having to
add more and more hooks to fakedb_test.go to simulate things
which real drivers end up doing.
Fixes#5323
R=golang-dev, snaury, gwenn.kahz, google, r
CC=golang-dev
https://golang.org/cl/8836045
From the issue, which describes it as well as I could:
database/sql assumes that driver.Stmt.Close does not need the
connection.
see database/sql/sql.go:1308:
This puts the Rows' connection back into the idle pool, and
then calls the driver.Stmt.Close method of the Stmt it belongs
to. In the postgresql driver implementation
(https://github.com/lib/pq), Stmt.Close communicates with the
server (on the connection that was just put back into the idle
pool). Most of the time, this causes no problems, but if
another goroutine makes a query at the right (wrong?) time,
chaos results.
In any case, traffic is being sent on "free" connections
shortly after they are freed, leading to race conditions that
kill the driver code.
Fixes#5283
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8633044
Completly the same like the Execer-Interface, just for Queries.
This allows Drivers to execute Queries without preparing them first
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7085056
Tests that here should be automatic retries if a database
driver's connection returns ErrBadConn on Begin. See
"TestTxErrBadConn" in sql_test.go
R=golang-dev
CC=golang-dev
https://golang.org/cl/6942050
Ran 'double.pl' on the pkg tree to identify doubled words.
One change to an error string return in x509; the rest are in comments.
Thanks to Matt Jibson for the idea.
R=golang-dev, bsiegert
CC=golang-dev
https://golang.org/cl/6344089
It was only being used for (*Stmt).Exec, not Query, and not for
the same two methods on *DB.
This unifies (*Stmt).Exec's old inline code into the old
subsetArgs function, renaming it in the process (changing the
old word "subset" to "driver", mostly converted earlier)
Fixes#3640
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6258045
To make sure that there is no resource leak,
I suggest to fix the 'fakedb' driver such as it fails when any
Stmt is not closed.
First, add a check in fakeConn.Close().
Then, fix all missing Stmt.Close()/Rows.Close().
I am not sure that the strategy choose in fakeConn.Prepare/prepare* is ok.
The weak point in this patch is the change in Tx.Query:
- Tests pass without this change,
- I found it by manually analyzing the code,
- I just try to make Tx.Query look like DB.Query.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5759050
In a transaction, on a Stmt.Query error, it was possible for a
connection to be added to a db's freelist twice. Should use
the local releaseConn function instead.
Thanks to Gwenael Treguier for the failing test.
Also in this CL: propagate driver errors through releaseConn
into *DB.putConn, which conditionally ignores the freelist
addition if the driver signaled ErrBadConn, introduced in a
previous CL.
R=golang-dev, gary.burd
CC=golang-dev
https://golang.org/cl/5798049
-- add driver.Value type and documentation,
convert from interface{} to Value where
appropriate.
-- don't say "subset" anywhere,
-- SubsetValuer -> Valuer
-- SubsetValue -> Value
-- IsParameterSubsetType -> IsValue
-- IsScanSubsetType -> IsScanValue
Fixes#2842
R=golang-dev, r, rsc
CC=golang-dev
https://golang.org/cl/5674084
