This var _ = log.Printf line was added 8 years ago, in CL 4973055,
which created the database/sql package and its tests. There was no
goimports back then, so this was likely added to make it easier to
use log package during development of tests.
It's no longer needed, so remove it. It can always be conveniently
re-added via goimports whenever needed.
Change-Id: I7c32ae3e593c194d970920084139dfa5a42386dc
Reviewed-on: https://go-review.googlesource.com/c/go/+/202481
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
It is common for database integers to be represented as int32
internally. Although NullInt64 is already defined,
this should remove some type casts and make working with those eaiser.
For #31231
Change-Id: Ia0c37ecef035fee0734c1d1fb6f58aef6905cf5e
Reviewed-on: https://go-review.googlesource.com/c/go/+/174178
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This CL add support for converting a returned cursor (presented
to this package as a driver.Rows) and scanning it into a *Rows.
Fixes#28515
Change-Id: Id8191c568dc135af9e5e8555efcd01987708edcb
Reviewed-on: https://go-review.googlesource.com/c/145738
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Ensure all error prefixes in the "database/sql" package start with
"sql: ". Do not prefix errors for type conversions because they
are always embedded in another error message with a specific
context.
Fixes#25251
Change-Id: I349d9804f3bfda4eeb755b32b508ec5992c28e07
Reviewed-on: https://go-review.googlesource.com/111637
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Previously we allowed drivers to modify the row buffer used to scan
values when closing Rows. This is no longer acceptable and can lead
to data races.
Fixes#23519
Change-Id: I91820a6266ffe52f95f40bb47307d375727715af
Reviewed-on: https://go-review.googlesource.com/89936
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
While driver.Connector was previously added to allow non-string
connection arguments and access to the context, most users of
the sql package will continue to rely on a string DSN.
Allow drivers to implement a string DSN to Connector interface
that both allows a single parsing of the string DSN and uses
the Connector interface which passes available context to
the driver dialer.
Fixes#22713
Change-Id: Ia0b862262f4c4670effe2538d0d6d43733fea18d
Reviewed-on: https://go-review.googlesource.com/77550
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Russ pointed out in a previous CL golang.org/cl/65731 that not only
was the locking incomplete, previous changes did not correctly
lock driver calls in other sections. After inspecting
driverConn, driverStmt, driverResult, Tx, and Rows structs
where driver interfaces are stored, I discovered a few more places
that failed to lock driver calls. The largest of these
was the parameter type converter "driverArgs".
driverArgs was typically called right before another call to the
driver in a locked region, so I made the entire driverArgs expect
a locked driver mutex and combined the region. This should not
be a problem because the connection is pulled out of the connection
pool either way so there shouldn't be contention.
Fixes#21117
Change-Id: I88d46f74dca25fb11a30f0bf8e79785a73133d23
Reviewed-on: https://go-review.googlesource.com/71433
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
A single database connection ususally maps to a single session.
A connection pool is logically also a session pool. Most
sessions have a way to reset the session state which is desirable
to prevent one bad query from poisoning another later query with
temp table name conflicts or other persistent session resources.
It also lets drivers provide users with better error messages from
queryies when the underlying transport or query method fails.
Internally the driver connection should now be marked as bad, but
return the actual connection. When ResetSession is called on the
connection it should return driver.ErrBadConn to remove it from
the connection pool. Previously drivers had to choose between
meaningful error messages or poisoning the connection pool.
Lastly update TestPoolExhaustOnCancel from relying on a
WAIT query fixing a flaky timeout issue exposed by this
change.
Fixes#22049Fixes#20807
Change-Id: I2b5df6d954a38d0ad93bf1922ec16e74c827274c
Reviewed-on: https://go-review.googlesource.com/73033
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This reverts commit 2620ac3aea.
Reason for revert: broke all the builds.
Change-Id: I26fc09a13f5f80fa708de66c843442ff9d934694
Reviewed-on: https://go-review.googlesource.com/73050
Reviewed-by: Russ Cox <rsc@golang.org>
A single database connection ususally maps to a single session.
A connection pool is logically also a session pool. Most
sessions have a way to reset the session state which is desirable
to prevent one bad query from poisoning another later query with
temp table name conflicts or other persistent session resources.
It also lets drivers provide users with better error messages from
queryies when the underlying transport or query method fails.
Internally the driver connection should now be marked as bad, but
return the actual connection. When ResetSession is called on the
connection it should return driver.ErrBadConn to remove it from
the connection pool. Previously drivers had to choose between
meaningful error messages or poisoning the connection pool.
Lastly update TestPoolExhaustOnCancel from relying on a
WAIT query fixing a flaky timeout issue exposed by this
change.
Fixes#22049Fixes#20807
Change-Id: Idffa1a7ca9ccfe633257c4a3ae299b864f46c5b6
Reviewed-on: https://go-review.googlesource.com/67630
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This reverts commit 897080d5cb.
Reason for revert: Fails to fix all the locking issues.
Updates #21117
Change-Id: I6fc9cb7897244d6e1af78c089a2bf383258ec049
Reviewed-on: https://go-review.googlesource.com/71450
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Database drivers should be called from a single goroutine to ease
driver's design. If a driver chooses to handle context
cancels internally it may do so.
The sql package violated this agreement when calling Next or
NextResultSet. It was possible for a concurrent rollback
triggered from a context cancel to call a Tx.Rollback (which
takes a driver connection lock) while a Rows.Next is in progress
(which does not tack the driver connection lock).
The current internal design of the sql package is each call takes
roughly two locks: a closemu lock which prevents an disposing of
internal resources (assigning nil or removing from lists)
and a driver connection lock that prevents calling driver code from
multiple goroutines.
Fixes#21117
Change-Id: Ie340dc752a503089c27f57ffd43e191534829360
Reviewed-on: https://go-review.googlesource.com/65731
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Rather then write to the same variable per fakeConn, write to either
fakeConn or rowsCursor.
Fixes#20646
Change-Id: Ifc79f989bd1606b8e3ebecb1e7844cce3ad06e17
Reviewed-on: https://go-review.googlesource.com/45393
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
In addition to adding a guard to the Rows close, add a var
in the fakeConn that gets read and written to on each
operation, simulating writing or reading from the server.
TestConcurrency/TxStmt* tests have been commented out
as they now fail after checking for races on the fakeConn.
See issue #20646 for more information.
Fixes#20622
Change-Id: I80b36ea33d776e5b4968be1683ff8c61728ee1ea
Reviewed-on: https://go-review.googlesource.com/45275
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Previously all arguments were passed through driver.IsValid.
This checked arguments against a few fundamental go types and
prevented others from being passed in as arguments.
The new interface driver.NamedValueChecker may be implemented
by both driver.Stmt and driver.Conn. This allows
this new interface to completely supersede the
driver.ColumnConverter interface as it can be used for
checking arguments known to a prepared statement and
arbitrary query arguments. The NamedValueChecker may be
skipped with driver.ErrSkip after all special cases are
exhausted to use the default argument converter.
In addition if driver.ErrRemoveArgument is returned
the argument will not be passed to the query at all,
useful for passing in driver specific per-query options.
Add a canonical Out argument wrapper to be passed
to OUTPUT parameters. This will unify checks that need to
be written in the NameValueChecker.
The statement number check is also moved to the argument
converter so the NamedValueChecker may remove arguments
passed to the query.
Fixes#13567Fixes#18079
Updates #18417
Updates #17834
Updates #16235
Updates #13067
Updates #19797
Change-Id: I89088bd9cca4596a48bba37bfd20d987453ef237
Reviewed-on: https://go-review.googlesource.com/38533
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Require parameter names to not begin with a symbol.
Change-Id: I5dfe9d4e181f0daf71dad2f395aca41c68678cbe
Reviewed-on: https://go-review.googlesource.com/33493
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Rather then using a sleep in the fake DB, go to a channel
select and wait for the context to be done.
Fixes#18115
Change-Id: I6bc3a29db58c568d0a7ea06c2a354c18c9e798b2
Reviewed-on: https://go-review.googlesource.com/33712
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
When context methods were initially added it was attempted to unify
behavior between drivers without Context methods and those with
Context methods to always return right away when the Context expired.
However in doing so the driver call could be executed outside of the
scope of the driver connection lock and thus bypassing thread safety.
The new behavior waits until the driver operation is complete. It then
checks to see if the context has expired and if so returns that error.
Change-Id: I4a5c7c3263420c57778f36a5ed6fa0ef8cb32b20
Reviewed-on: https://go-review.googlesource.com/32422
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Creates a ColumnType structure that can be extended in to future.
Allow drivers to implement what makes sense for the database.
Fixes#16652
Change-Id: Ieb1fd64eac1460107b1d3474eba5201fa300a4ec
Reviewed-on: https://go-review.googlesource.com/29961
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Modify the new Context methods to take a name-value driver struct.
This will require more modifications to drivers to use, but will
reduce the overall number of structures that need to be maintained
over time.
Fixes#12381
Change-Id: I30747533ce418a1be5991a0c8767a26e8451adbd
Reviewed-on: https://go-review.googlesource.com/30166
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Many database systems allow returning multiple result sets
in a single query. This can be useful when dealing with many
intermediate results on the server and there is a need
to return more then one arity of data to the client.
Fixes#12382
Change-Id: I480a9ac6dadfc8743e0ba8b6d868ccf8442a9ca1
Reviewed-on: https://go-review.googlesource.com/30592
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.
This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:
$ perl -i -npe 's,^(\s*// .+[a-z]\.) +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.) +([A-Z])')
$ go test go/doc -update
Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
For #13677, but there is more to do.
Change-Id: Id1af999dc972d07cdfc771e5855a1a7dca47ca96
Reviewed-on: https://go-review.googlesource.com/18046
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Previously with db.maxOpen > 0, db.maxOpen+n failed connection attempts
started concurrently could result in a deadlock. DB.conn and
DB.openNewConnection did not trigger the DB.connectionOpener go routine
after a failed connection attempt. This omission could leave go routines
waiting for DB.connectionOpener forever.
In addition the logic to track the state of the pool was inconsistent.
db.numOpen was sometimes incremented optimistically and sometimes not.
This change harmonizes the logic and eliminates the db.pendingOpens
variable, making the logic easier to understand and maintain.
Fixes#10886
Change-Id: I983c4921a3dacfbd531c3d7f8d2da8a592e9922a
Reviewed-on: https://go-review.googlesource.com/14547
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Previously Tx.close always passed a nil error to tx.db.putConn. As a
result bad connections were reused, even if the driver returned
driver.ErrBadConn. Adding an err parameter to Tx.close allows it to
receive the driver error from Tx.Commit and Tx.Rollback and pass it
to tx.db.putConn.
Fixes#11264
Change-Id: I142b6b2509fa8d714bbc135cef7281a40803b3b8
Reviewed-on: https://go-review.googlesource.com/13912
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Previously if the connection pool was larger than maxBadConnRetries
and there were a lot of bad connections in the pool (for example if
the database server was restarted), a query might have failed with an
ErrBadConn unnecessarily. Instead of trying to guess how many times
to retry, try maxBadConnRetries times and then force a fresh
connection to be used for the last attempt. At the same time, lower
maxBadConnRetries to a smaller value now that it's not that important
to retry so many times from the free connection list.
Fixes#8834
Change-Id: I6542f151a766a658980fb396fa4880ecf5874e3d
Reviewed-on: https://go-review.googlesource.com/2034
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
