While it is possible for the connection pool to guard against panics
on every valuer read, this seems like a high cost to be added,
in both code complexity and possible runtime performance.
Most uses of the Valuer will be trivial, like returning
a struct field. Optimize for that case. If sometime may panic the
valuer should itself use recover and return an error.
Fixes#26332
Change-Id: Iad18780b8028f669f5a7841b74a5384d62fb6a7e
Reviewed-on: https://go-review.googlesource.com/c/go/+/170700
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Most changes are removing redundant declaration of type when direct
instantiating value of map or slice, e.g. []T{T{}} become []T{{}}.
Small changes are removing the high order of subslice if its value
is the length of slice itself, e.g. T[:len(T)] become T[:].
The following file is excluded due to incompatibility with go1.4,
- src/cmd/compile/internal/gc/ssa.go
Change-Id: Id3abb09401795ce1e6da591a89749cba8502fb26
Reviewed-on: https://go-review.googlesource.com/c/go/+/166437
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@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>
A nil src (NULL database value) will result in a "nil" string,
which will never parse correctly in a ParseInt or similar
numeric conversion. The resulting error is confusing. Check
for a nil src prior to converting the value to string
if the resulting string will be parsed after that.
Closes#31274
Change-Id: I90f12cceff00fbbfdd3e343b04fa7e2596390e6d
Reviewed-on: https://go-review.googlesource.com/c/go/+/174177
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Though there is variation in the spelling of canceled,
cancellation is always spelled with a double l.
Reference: https://www.grammarly.com/blog/canceled-vs-cancelled/
Change-Id: I240f1a297776c8e27e74f3eca566d2bc4c856f2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/170060
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
When prepared on a DB, prepared statement code in database/sql handles everything to keep the prepared statement alive as it moves across the connection pool. Understanding this is an important part of using this API correctly, but it was only documented indirectly via `(*Tx) Prepare*`.
Change-Id: Ic8757e0150d59e675d9f0252f6c15aef2cc2e831
GitHub-Last-Rev: 55dba87458
GitHub-Pull-Request: golang/go#29890
Reviewed-on: https://go-review.googlesource.com/c/159077
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
The logic for pulling a database connection from the DB pool should
proceed as follows: attempt to pull either a cached connection or
new connection N times in a loop. If each connection results
in a bad connection, then create a new connection (no cache).
Previously pulling a Conn from the pool, the last step also
looked at the cache, rather then always creating a new connection.
Fixes#29684
Change-Id: I8f436fd9b96eb35502a620ebe8da4ab89fb06a2e
Reviewed-on: https://go-review.googlesource.com/c/157637
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Show two larger application examples. One example that
could be used in a CLI, the other in a long running
service. These demonstarates different strategies for
handling DB.Ping errors in context.
Fixes#23738
Change-Id: Id01213caf1f47917239a7506b01d30e37db74d31
Reviewed-on: https://go-review.googlesource.com/c/101216
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>
Go documentation style for boolean funcs is to say:
// Foo reports whether ...
func Foo() bool
(rather than "returns true if")
This CL also replaces 4 uses of "iff" with the same "reports whether"
wording, which doesn't lose any meaning, and will prevent people from
sending typo fixes when they don't realize it's "if and only if". In
the past I think we've had the typo CLs updated to just say "reports
whether". So do them all at once.
(Inspired by the addition of another "returns true if" in CL 146938
in fd_plan9.go)
Created with:
$ perl -i -npe 's/returns true if/reports whether/' $(git grep -l "returns true iff" | grep -v vendor)
$ perl -i -npe 's/returns true if/reports whether/' $(git grep -l "returns true if" | grep -v vendor)
Change-Id: Ided502237f5ab0d25cb625dbab12529c361a8b9f
Reviewed-on: https://go-review.googlesource.com/c/147037
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The old one was rather confusing - it makes it sound like the user has done something wrong.
Change-Id: Ibc7411f4f1d5f6c66fbcaac64bb05b0743354418
GitHub-Last-Rev: 09290accdd
GitHub-Pull-Request: golang/go#27979
Reviewed-on: https://go-review.googlesource.com/c/139102
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Previously the MaxIdleClosed counter was incremented when added
to the free connection list, rather then when it wasn't added
to the free connection list. Flip this logic to correct.
Fixes#27792
Change-Id: I405302c14fb985369dab48fbe845e5651afc4ccf
Reviewed-on: https://go-review.googlesource.com/c/138578
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
It was unclear that users must copy values out of the src value
for value types like []byte.
Fixes#24492
Change-Id: I99ad61e0ad0075b9efc5ee4e0d067f752f91b8fa
Reviewed-on: https://go-review.googlesource.com/108535
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Provide better statistics for the database pool. Add counters
for waiting on the pool and closes. Too much waiting or too many
connection closes could indicate a problem.
Fixes#24683Fixes#22138
Change-Id: I9e1e32a0487edf41c566b8d9c07cb55e04078fec
Reviewed-on: https://go-review.googlesource.com/108536
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The connRequest may return a nil conn value. However in a rare
case that is difficult to test for it was being passed to
DB.putConn without a nil check. This was an error as this
made no sense if the driverConn is nil. This also caused
a panic in putConn.
A test for this would be nice, but didn't find a sane
way to test for this condition.
Fixes#24445
Change-Id: I827316e856788a5a3ced913f129bb5869b7bcf68
Reviewed-on: https://go-review.googlesource.com/102477
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alexey Palazhchenko <alexey.palazhchenko@gmail.com>
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>
Fixes golint warning about "if block ends with a return statement,
so drop this else and outdent its block".
Change-Id: Iac4fd324e04e3e3fe3e3933f5e59095041d292c5
Reviewed-on: https://go-review.googlesource.com/107115
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This commit includes efficiency improvements in two places in the
database/sql package where an "if err != nil" was redundant and
the error can be returned as-is (most of the code in the standard
library and even in the file I changed does it my suggested way).
Change-Id: Ib9dac69ed01ee846e570a776164cb87c2caee6ca
Reviewed-on: https://go-review.googlesource.com/106555
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The previous implementation would return "sql: Rows are closed" for any
context errors, which can be confusing for context timeouts or
cancelations.
Fixes#24431
Change-Id: I884904ec43204c43f4e94e2335b2802aab77a888
Reviewed-on: https://go-review.googlesource.com/104276
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
It wasn't clear for existing docs if DB.Close forcefully closed
connections or waited for them to finish.
Fixes#23753
Change-Id: Id7df31224c93181c8d01bab7b0b23da25b42a288
Reviewed-on: https://go-review.googlesource.com/103397
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Prevent queries from starting a goroutine if the context is
not able to be canceled.
Fixes#23879
Change-Id: I392047bd53d7f796219dd12ee11b07303658fdaf
Reviewed-on: https://go-review.googlesource.com/102478
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Yasuhiro MATSUMOTO <mattn.jp@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This aims to expand the coverage of examples showing how the sql
package works, as well as to address a number of issues I've observed
while explaining how the database package works:
- The best way to issue UPDATE or INSERT queries, that don't need
to scan anything in return. (Previously, we had no examples for any
Execute statement).
- How to use prepared statements and transactions.
- How to aggregate arguments from a Query/QueryContext query into
a slice.
Furthermore just having examples in more places should help, as users
click on e.g. the "Rows" return parameter and are treated with the
lack of any example about how Rows is used.
Switch package examples to use QueryContext/QueryRowContext; I think
it is a good practice to prepare users to issue queries with a timeout
attached, even if they are not using it immediately.
Change-Id: I4e63af91c7e4fff88b25f820906104ecefde4cc3
Reviewed-on: https://go-review.googlesource.com/91015
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Since https://golang.org/cl/38533, this validation is performed in
driverArgs.
Change-Id: I13a3ca46a1aa3197370de1095fb46ab83ea4628c
Reviewed-on: https://go-review.googlesource.com/91115
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When 'convertAssign' gives an error, instead of giving just the index of
the failing column -- which is not always helpful, especially when there
are lots of columns in the query -- utilize 'rs.rowsi.Columns()' to
extract the underlying column name and include that in the error string:
sql: Scan error on column index 0, name "some_column": ...
Fixes#23362
Change-Id: I0fe71ff3c25f4c0dd9fc6aa2c2da2360dd93e3e0
Reviewed-on: https://go-review.googlesource.com/86537
Reviewed-by: Harald Nordgren <haraldnordgren@gmail.com>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@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>
Provide a fresh conversion table for TestConversions as it gets
modified on each test.
Change-Id: I6e2240d0c3455451271a6879e994b82222c3d44c
Reviewed-on: https://go-review.googlesource.com/89595
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
During the refactor in 1126d1483f I
introduced a logical error within one withLock function that used
the result of the call before checking for the error. Change
the order so that the error is checked before the result is used.
None of the other withLock uses have similar issues.
Fixes#23208
Change-Id: I6c5dcf262e36bad4369c850f1e0131066360a82e
Reviewed-on: https://go-review.googlesource.com/85175
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Caleb Spare <cespare@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The driver.Value type may be more then the documented 6 types if the
database driver supports it. Document that fact.
Updates #23077
Change-Id: If7e2112fa61a8cc4e155bb31e94e89b20c607242
Reviewed-on: https://go-review.googlesource.com/84636
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The docs make it seem like they are all things a single object
would implement. That's true of Driver and DriverContext,
but Connector is really something else. Attempt to clarify.
Change-Id: I8fdf1cff855a0fbe37ea22720c082045c719a267
Reviewed-on: https://go-review.googlesource.com/82082
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
When the user context which passed in (*DB)BeginTx is canceled or
timeout, the current implementation could cause db transaction leak
in some extreme scenario.
Goroutine 1:
Call (*DB) BeginTx begins a transaction with a userContext.
In (*DB)BeginTx, a new goroutine (*Tx)awaitDone
which monitor context and rollback tx if needed will be created
Goroutine 2(awaitDone):
block on tx.ctx.Done()
Goroutine 1:
Execute some insert or update sqls on the database
Goroutine 1:
Commit the transaction, (*Tx)Commit set
the atomic variable tx.done to 1
Goroutine 3(maybe global timer):
Cancel userContext which be passed in Tx
Goroutine 1:
(*Tx)Commit checks tx.ctx.Done().
Due to the context has been canceled, it will return
context.Canceled or context.DeadlineExceeded error immediately
and abort the real COMMIT operation of transaction
Goroutine 2:
Release with tx.ctx.Done() signal, execute (*Tx)rollback.
However the atomic variable tx.done is 1 currently,
it will return ErrTxDone error immediately and
abort the real ROLLBACK operation of transaction
Fixes#22976
Change-Id: I3bc23adf25db823861d91e33d3cca6189fb1171d
Reviewed-on: https://go-review.googlesource.com/81736
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Check for the expected number of arguments in a SQL statement
after arguments are eliminated in the argument converter.
This situation was already tested for in TestNamedValueChecker.
However the test used Exec which didn't have any check for
NumInput on it at all, thus this issue was never caught.
In addition to moving the NumInput check on the Query
methods after the converter, add the NumInput check
to the Exec methods as well.
Fixes#22630
Change-Id: If45920c6e1cf70dca63822a0cedec2cdc5cc611c
Reviewed-on: https://go-review.googlesource.com/76732
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@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>
CL 21663 allowed drivers to implement ExecerContext without
also implementing Execer, and similarly QueryerContext without
Queryer, but it did not make that clear in the documentation.
This CL updates the documentation.
Change-Id: I9a4accaac32edfe255fe7c0b0907d4c1014322b4
Reviewed-on: https://go-review.googlesource.com/78129
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
ctx.Done() == ctx.Background().Done() is just
a long way to write ctx.Done() == nil.
Use the short way.
Change-Id: I7b3198b5dc46b8b40086243aa61882bc8c268eac
Reviewed-on: https://go-review.googlesource.com/78128
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Originally we tried the strict -er suffix as the rule in this case
but eventually we decided it was too awkward: io.WriteByter
became io.ByteWriter. By analogy, here the interface should be
named SessionResetter instead of the awkward ResetSessioner.
This change should not affect any drivers that have already
implemented the interface, because the method name is not changing.
(This was added during the Go 1.10 cycle and has not been
released yet, so we can change it.)
Change-Id: Ie50e4e090d3811f85965da9da37d966e9f45e79d
Reviewed-on: https://go-review.googlesource.com/78127
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Before terminating the connectionResetter goroutine the connection
pool processes all of the connections on the channel to unlock the
driverConn instances so everthing can shutdown cleanly. However
the channel was never closed so the goroutine hangs on the range.
Close the channel prior to ranging over it. Also prevent additional
connections from being sent to the resetter after the connection
pool has been closed.
Fixes#22699
Change-Id: I440d2b13cbedec2e04621557f5bd0b1526933dd7
Reviewed-on: https://go-review.googlesource.com/77390
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The go repository contains a mix of github.com/golang/go/issues/xxxxx
and golang.org/issues/xxxxx URLs for references to issues in the issue
tracker. We should use one for consistency, and golang.org is preferred
in case the project moves the issue tracker in the future.
This reasoning is taken from a comment Sam Whited left on a CL I
recently opened: https://go-review.googlesource.com/c/go/+/73890.
In that CL I referenced an issue using its github.com URL, because other
tests in the file I was changing contained references to issues using
their github.com URL. Sam Whited left a comment on the CL stating I
should change it to the golang.org URL.
If new code is intended to reference issues via golang.org and not
github.com, existing code should be updated so that precedence exists
for contributors who are looking at the existing code as a guide for the
code they should write.
Change-Id: I3b9053fe38a1c56fc101a8b7fd7b8f310ba29724
Reviewed-on: https://go-review.googlesource.com/75673
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Previously scanning time.Time into a *time.Time required reflection.
Now it does not. Scanning already checked if the source value was of
type time.Time. The only addition was checking the destination was
of type *time.Time.
Existing tests already scan time.Time into *time.Time, so no new
tests were added. Linked issue has performance justification.
Fixes#22300
Change-Id: I4eea461c78fad71ce76e7677c8503a1919666931
Reviewed-on: https://go-review.googlesource.com/73232
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@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>
Drivers shouldn't need to implement both Queryer and QueryerContext,
they should just implement QueryerContext. Same with Execer and
ExecerContext. This CL tests for QueryContext and ExecerContext
first so drivers do not need to implement Queryer and Execer
with an empty definition.
Fixes#21663
Change-Id: Ifbaa71da669f4bc60f8da8c41a04a4afed699a9f
Reviewed-on: https://go-review.googlesource.com/65733
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>
Before this change the ct == 0 check could never be true. Moreover the
values were not properly indirected.
Change-Id: Ice47e36e3492babc4b47d2f9099e8772be231c96
Reviewed-on: https://go-review.googlesource.com/68130
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
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A new switch case for converting the source string type into a
destination RawBytes type avoids the reflection based conversion.
Speed up from old ~61.7ns/op down to ~49ns/op.
A second new switch case allows to convert and assign a source time.Time
type into a destination sql.RawBytes type. This switch case appends
the time to the reset RawBytes slice. This allows the reuse of RawBytes
and avoids allocations.
Fixes#20746
Change-Id: Ib0563fd5c5c7cb6d9d0acaa1d9aa7b2927f1329c
Reviewed-on: https://go-review.googlesource.com/66830
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
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Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
The fields wantbytes and wantraw in the test struct `conversionTest` has
been forgotten to include in the TestConversions function.
Change-Id: I6dab69e76de3799a1bbf9fa09a15607e55172114
Reviewed-on: https://go-review.googlesource.com/66610
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
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Replace the work "session" with "connection" in docs. Fix
The ErrConnDone documentation. Clarify what the context is used
for in StmtContext.
Change-Id: I2f07e58d0cd6321b386a73b038cf6070cb8e2572
Reviewed-on: https://go-review.googlesource.com/65732
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The current Open method limits the ability for driver maintainers
to expose options for their drivers by forcing all the configuration
to pass through the DSN in order to create a *DB.
This CL allows driver maintainers to write their own initialization
functions that return a *DB making configuration of the underlying
drivers easier.
Fixes#20268
Change-Id: Ib10b794f36a201bbb92c23999c8351815d38eedb
Reviewed-on: https://go-review.googlesource.com/53430
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
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Currently, the check for `ctx.Done() == context.Background().Done()`
comes before the check to see if we are ignoring any options. That
check should be done earlier, so that the options are not silently
ignored.
Fixes#21350
Change-Id: I3704e4209854c7d99f3f92498bae831cabc7e419
Reviewed-on: https://go-review.googlesource.com/53970
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
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Ensure a Stmt prepared on a Conn executes on the same driver.Conn.
This also removes another instance of duplicated prepare logic
as a side effect.
Fixes#20647
Change-Id: Ia00a19e4dd15e19e4d754105babdff5dc127728f
Reviewed-on: https://go-review.googlesource.com/45391
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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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>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The Tx methods Query and Exec uses context.Background()
even Tx was created by context.
This patch enables using Tx.ctx in all Tx methods
which do not has context arg.
Backward compatibility:
- If Tx has created without context, nothing changes.
- If Tx has created with context and non-context method is called:
- If context is expired, the execution fails,
but it can fail on Commit or Rollback as well,
so in terms of whole transaction - nothing changes.
- If context is not expired, nothing changes too.
Fixes#20098
Change-Id: I9570a2deaace5875bb4c5dcf7b3a084a6bcd0d00
Reviewed-on: https://go-review.googlesource.com/44956
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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Close any Rows queried within a Tx when the Tx is closed. This prevents
the Tx from blocking on rollback if a Rows query has not been closed yet.
Fixes#20575
Change-Id: I4efe9c4150e951d8a0f1c40d9d5e325964fdd608
Reviewed-on: https://go-review.googlesource.com/44812
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Query and Exec functions on DB first attempt to get a cached
connection before requesting the connection pool to ignore
the cache and get a new connection. This change aligns Stmt to
that behavior as well.
Fixes#20433
Change-Id: Idda5f61927289d7ad0882effa3a50ffc9efd88e6
Reviewed-on: https://go-review.googlesource.com/43790
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>
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When running a Query on Stmt a dependency is added to the stmt and
rows. To do that it needs a reference to Rows, so the releaseConn
function is defined after the definition. However the
rows.initContextClose was set to run before the releaseConn was
set on rows, setting up a situation where the connection could
be canceled before the releaseConn was set and resulting in
a segfault.
Fixes#20160
Change-Id: I5592e7db2cf653dfc48d42cbc2b03ca20501b1a0
Reviewed-on: https://go-review.googlesource.com/42139
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Databases have the following concepts: Statement, Batch, and Session.
A statement is often a single line like:
SELECT Amount from Account where ID = 50;
A batch is one or more statements submitted together for the query
to process. It may be a DELETE, INSERT, two UPDATES and a SELECT in
a single query text.
A session is usually represented by a single database connection.
This often is an issue when dealing with scopes in databases.
Temporary tables and variables can have batch, session, or global
scope depending on the syntax, database, and use.
Furthermore, some databases (sybase and derivatives in perticular)
that prevent certain statements from being in the same batch
and may necessitate being in the same session.
By allowing users to extract a Conn from the database they can manage
session on their own without hacking around it by making connection
pools of single connections (a real workaround presented in issue).
It is tempting to just use a transaction, but this isn't always
desirable or an option if running an interactive session or
alter script set that itself starts transactions.
Fixes#18081
Change-Id: I9bdf0796632c48d4bcaef3624c629641984ffaf2
Reviewed-on: https://go-review.googlesource.com/40694
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
When a Tx starts a query, prevent returning the connection to the pool
until after the query finishes.
Fixes#19058
Change-Id: I2c0480d9cca9eeb173b5b3441a5aeed6f527e0ac
Reviewed-on: https://go-review.googlesource.com/40400
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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Form a new method pattern where *driverConn and
release functions are passed into the method.
They are named DB.execDC, DB.queryDC, DB.beginDC. This
allows more code to be de-duplicated when starting
queries.
The Stmt creation and management code are untouched.
Change-Id: I24c853531e511d8a4bc1f53dd4dbdf968763b4e7
Reviewed-on: https://go-review.googlesource.com/39630
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
User defined numeric types such as "type Int int64" have
been able to be scanned into without a custom scanner by
using the reflect scan code path used to convert between
various numeric types. Add in a path for string types
for symmetry and least surprise.
Fixes#18101
Change-Id: I00553bcf021ffe6d95047eca0067ee94b54ff501
Reviewed-on: https://go-review.googlesource.com/39031
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This change was originally written by Marko Tiikkaja <marko@joh.to>.
https://go-review.googlesource.com/#/c/2035/
Previously *Tx.Stmt always prepared a new statement, even if an
existing one was available on the connection the transaction was on.
Now we first see if the statement is already available on the
connection and only prepare if it isn't. Additionally, when we do
need to prepare one, we store it in the parent *Stmt to allow it to be
later reused by other calls to *Tx.Stmt on that statement or just
straight up by *Stmt.Exec et al.
To make sure that the statement doesn't disappear unexpectedly, we
record a dependency from the statement returned by *Tx.Stmt to the
*Stmt it came from and set a new field, parentStmt, to point to the
originating *Stmt. When the transaction's *Stmt is closed, we remove
the dependency. This way the "parent" *Stmt can be closed by the user
without her having to know whether any transactions are still using it
or not.
Fixes#15606
Change-Id: I41b5056847e117ac61130328b0239d1e000a4a08
Reviewed-on: https://go-review.googlesource.com/35476
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
When testing context cancelation behavior do not rely on context
timeouts. Use explicit checks in all such tests. In closeDB
convert the simple check for zero open conns with a wait loop
for zero open conns.
Fixes#19024Fixes#19041
Change-Id: Iecfcc4467e91249fceb21ffd1f7c62c58140d8e9
Reviewed-on: https://go-review.googlesource.com/36902
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Previously if a connection was requested but timed out during the
request and when acquiring the db.Lock the connection request
is fulfilled and the request is unable to be returned to the
connection pool, then then driver connection would not be closed.
No tests were added or modified because I was unable to determine
how to trigger this situation without something invasive.
Change-Id: I9d4dc680e3fdcf63d79d212174a5b8b313f363f1
Reviewed-on: https://go-review.googlesource.com/36641
Reviewed-by: Russ Cox <rsc@golang.org>
Previously if a context was canceled while it was waiting for a
connection request, that connection request would leak.
To prevent this remove the pending connection request if the
context is canceled and ensure no connection has been sent on the channel.
This requires a change to how the connection requests are represented in the DB.
Fixes#18995
Change-Id: I9a274b48b8f4f7ca46cdee166faa38f56d030852
Reviewed-on: https://go-review.googlesource.com/36563
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Previously it was intended that Rows.Scan would return
an error and Rows.Err would return nil. This was problematic
because drivers could not differentiate between a normal
Rows.Close or a context cancel close.
The alternative is to require drivers to return a Scan to return
an error if the driver is closed while there are still rows to be read.
This is currently not how several drivers currently work and may be
difficult to detect when there are additional rows.
At the same time guard the the Rows.lasterr and prevent a close
while a Rows operation is active.
For the drivers that do not have Context methods, do not check for
context cancelation after the operation, but before for any operation
that may modify the database state.
Fixes#18961
Change-Id: I49a25318ecd9f97a35d5b50540ecd850c01cfa5e
Reviewed-on: https://go-review.googlesource.com/36485
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Daniel Theophanes
Brad Fitzpatrick
Shulhan
Josh Bleecher Snyder
Hasan Ozgan
Andrei Matei
Zhou Peng
Justin Li
Tobias Klauser
Vladimir Kovpak
Umang Parmar
Igor Zhilianin
Tim
Alexey Palazhchenko
Frédéric Guillot
Eugene Kalinin
weeellz
dchenk
Eric Rykwalder
Andrew Bonventre
Kevin Burke
Shawn Smith
Ryuma Yoshida
Tamir Duberstein
HaraldNordgren
Russ Cox
kirk
Leigh McCulloch
Tim Cooper
Julien Schmidt
Cyrill Schumacher
James Lawrence
Davor Kapsa
Agniva De Sarker
Matt Dee
Martin Garton
Sarah Adams
Bulat Gaifullin
Mikio Hara