Documentation ¶
Overview ¶
Package sqlite is a sql/database driver using a CGo-free port of the C SQLite3 library.
SQLite is an in-process implementation of a self-contained, serverless, zero-configuration, transactional SQL database engine.
Thanks ¶
This project is sponsored by Schleibinger Geräte Teubert u. Greim GmbH by allowing one of the maintainers to work on it also in office hours.
Supported platforms and architectures ¶
These combinations of GOOS and GOARCH are currently supported
OS Arch SQLite version ------------------------------ darwin amd64 3.41.2 darwin arm64 3.41.2 freebsd amd64 3.41.2 freebsd arm64 3.41.2 linux 386 3.41.2 linux amd64 3.41.2 linux arm 3.41.2 linux arm64 3.41.2 linux ppc64le 3.41.2 linux riscv64 3.41.2 linux s390x 3.41.2 windows amd64 3.41.2 windows arm64 3.41.2
Builders ¶
Builder results available at:
https://modern-c.appspot.com/-/builder/?importpath=modernc.org%2fsqlite
Speedtest1 ¶
Numbers for the pure Go version were produced by
~/src/modernc.org/sqlite/speedtest1$ go build && ./speedtest1
Numbers for the pure C version were produced by
~/src/modernc.org/sqlite/testdata/sqlite-src-3410200/test$ gcc speedtest1.c ../../sqlite-amalgamation-3410200/sqlite3.c -lpthread -ldl && ./a.out
The results are from Go version 1.20.4 and GCC version 10.2.1 on a Linux/amd64 machine, CPU: AMD Ryzen 9 3900X 12-Core Processor × 24, 128GB RAM. Shown are the best of 3 runs.
Go C -- Speedtest1 for SQLite 3.41.2 2023-03-22 11:56:21 0d1fc92f94cb6b76bffe3ec34d69 -- Speedtest1 for SQLite 3.41.2 2023-03-22 11:56:21 0d1fc92f94cb6b76bffe3ec34d69 100 - 50000 INSERTs into table with no index...................... 0.071s 100 - 50000 INSERTs into table with no index...................... 0.077s 110 - 50000 ordered INSERTS with one index/PK..................... 0.114s 110 - 50000 ordered INSERTS with one index/PK..................... 0.082s 120 - 50000 unordered INSERTS with one index/PK................... 0.137s 120 - 50000 unordered INSERTS with one index/PK................... 0.099s 130 - 25 SELECTS, numeric BETWEEN, unindexed...................... 0.083s 130 - 25 SELECTS, numeric BETWEEN, unindexed...................... 0.091s 140 - 10 SELECTS, LIKE, unindexed................................. 0.210s 140 - 10 SELECTS, LIKE, unindexed................................. 0.120s 142 - 10 SELECTS w/ORDER BY, unindexed............................ 0.276s 142 - 10 SELECTS w/ORDER BY, unindexed............................ 0.182s 145 - 10 SELECTS w/ORDER BY and LIMIT, unindexed.................. 0.183s 145 - 10 SELECTS w/ORDER BY and LIMIT, unindexed.................. 0.099s 150 - CREATE INDEX five times..................................... 0.172s 150 - CREATE INDEX five times..................................... 0.127s 160 - 10000 SELECTS, numeric BETWEEN, indexed..................... 0.080s 160 - 10000 SELECTS, numeric BETWEEN, indexed..................... 0.078s 161 - 10000 SELECTS, numeric BETWEEN, PK.......................... 0.080s 161 - 10000 SELECTS, numeric BETWEEN, PK.......................... 0.078s 170 - 10000 SELECTS, text BETWEEN, indexed........................ 0.187s 170 - 10000 SELECTS, text BETWEEN, indexed........................ 0.169s 180 - 50000 INSERTS with three indexes............................ 0.196s 180 - 50000 INSERTS with three indexes............................ 0.154s 190 - DELETE and REFILL one table................................. 0.200s 190 - DELETE and REFILL one table................................. 0.155s 200 - VACUUM...................................................... 0.180s 200 - VACUUM...................................................... 0.142s 210 - ALTER TABLE ADD COLUMN, and query........................... 0.004s 210 - ALTER TABLE ADD COLUMN, and query........................... 0.005s 230 - 10000 UPDATES, numeric BETWEEN, indexed..................... 0.093s 230 - 10000 UPDATES, numeric BETWEEN, indexed..................... 0.080s 240 - 50000 UPDATES of individual rows............................ 0.153s 240 - 50000 UPDATES of individual rows............................ 0.137s 250 - One big UPDATE of the whole 50000-row table................. 0.024s 250 - One big UPDATE of the whole 50000-row table................. 0.019s 260 - Query added column after filling............................ 0.004s 260 - Query added column after filling............................ 0.005s 270 - 10000 DELETEs, numeric BETWEEN, indexed..................... 0.278s 270 - 10000 DELETEs, numeric BETWEEN, indexed..................... 0.263s 280 - 50000 DELETEs of individual rows............................ 0.188s 280 - 50000 DELETEs of individual rows............................ 0.180s 290 - Refill two 50000-row tables using REPLACE................... 0.411s 290 - Refill two 50000-row tables using REPLACE................... 0.359s 300 - Refill a 50000-row table using (b&1)==(a&1)................. 0.175s 300 - Refill a 50000-row table using (b&1)==(a&1)................. 0.151s 310 - 10000 four-ways joins....................................... 0.427s 310 - 10000 four-ways joins....................................... 0.365s 320 - subquery in result set...................................... 0.440s 320 - subquery in result set...................................... 0.521s 400 - 70000 REPLACE ops on an IPK................................. 0.125s 400 - 70000 REPLACE ops on an IPK................................. 0.106s 410 - 70000 SELECTS on an IPK..................................... 0.081s 410 - 70000 SELECTS on an IPK..................................... 0.078s 500 - 70000 REPLACE on TEXT PK.................................... 0.174s 500 - 70000 REPLACE on TEXT PK.................................... 0.116s 510 - 70000 SELECTS on a TEXT PK.................................. 0.153s 510 - 70000 SELECTS on a TEXT PK.................................. 0.117s 520 - 70000 SELECT DISTINCT....................................... 0.083s 520 - 70000 SELECT DISTINCT....................................... 0.067s 980 - PRAGMA integrity_check...................................... 0.436s 980 - PRAGMA integrity_check...................................... 0.377s 990 - ANALYZE..................................................... 0.107s 990 - ANALYZE..................................................... 0.038s TOTAL....................................................... 5.525s TOTAL....................................................... 4.637s
This particular test executes 16.1% faster in the C version.
Changelog ¶
2023-08-03 v1.25.0: enable SQLITE_ENABLE_DBSTAT_VTAB.
2023-07-11 v1.24.0:
Add (*conn).{Serialize,Deserialize,NewBackup,NewRestore} methods, add Backup type.
2023-06-01 v1.23.0:
Allow registering aggregate functions.
2023-04-22 v1.22.0:
Support linux/s390x.
2023-02-23 v1.21.0:
Upgrade to SQLite 3.41.0, release notes at https://sqlite.org/releaselog/3_41_0.html.
2022-11-28 v1.20.0
Support linux/ppc64le.
2022-09-16 v1.19.0:
Support frebsd/arm64.
2022-07-26 v1.18.0:
Adds support for Go fs.FS based SQLite virtual filesystems, see function New in modernc.org/sqlite/vfs and/or TestVFS in all_test.go
2022-04-24 v1.17.0:
Support windows/arm64.
2022-04-04 v1.16.0:
Support scalar application defined functions written in Go.
https://www.sqlite.org/appfunc.html
2022-03-13 v1.15.0:
Support linux/riscv64.
2021-11-13 v1.14.0:
Support windows/amd64. This target had previously only experimental status because of a now resolved memory leak.
2021-09-07 v1.13.0:
Support freebsd/amd64.
2021-06-23 v1.11.0:
Upgrade to use sqlite 3.36.0, release notes at https://www.sqlite.org/releaselog/3_36_0.html.
2021-05-06 v1.10.6:
Fixes a memory corruption issue (https://gitlab.com/cznic/sqlite/-/issues/53). Versions since v1.8.6 were affected and should be updated to v1.10.6.
2021-03-14 v1.10.0:
Update to use sqlite 3.35.0, release notes at https://www.sqlite.org/releaselog/3_35_0.html.
2021-03-11 v1.9.0:
Support darwin/arm64.
2021-01-08 v1.8.0:
Support darwin/amd64.
2020-09-13 v1.7.0:
Support linux/arm and linux/arm64.
2020-09-08 v1.6.0:
Support linux/386.
2020-09-03 v1.5.0:
This project is now completely CGo-free, including the Tcl tests.
2020-08-26 v1.4.0:
First stable release for linux/amd64. The database/sql driver and its tests are CGo free. Tests of the translated sqlite3.c library still require CGo.
$ make full ... SQLite 2020-08-14 13:23:32 fca8dc8b578f215a969cd899336378966156154710873e68b3d9ac5881b0ff3f 0 errors out of 928271 tests on 3900x Linux 64-bit little-endian WARNING: Multi-threaded tests skipped: Linked against a non-threadsafe Tcl build All memory allocations freed - no leaks Maximum memory usage: 9156360 bytes Current memory usage: 0 bytes Number of malloc() : -1 calls --- PASS: TestTclTest (1785.04s) PASS ok modernc.org/sqlite 1785.041s $
2020-07-26 v1.4.0-beta1:
The project has reached beta status while supporting linux/amd64 only at the moment. The 'extraquick' Tcl testsuite reports
630 errors out of 200177 tests on Linux 64-bit little-endian
and some memory leaks
Unfreed memory: 698816 bytes in 322 allocations
2019-12-28 v1.2.0-alpha.3: Third alpha fixes issue #19.
It also bumps the minor version as the repository was wrongly already tagged with v1.1.0 before. Even though the tag was deleted there are proxies that cached that tag. Thanks /u/garaktailor for detecting the problem and suggesting this solution.
2019-12-26 v1.1.0-alpha.2: Second alpha release adds support for accessing a database concurrently by multiple goroutines and/or processes. v1.1.0 is now considered feature-complete. Next planed release should be a beta with a proper test suite.
2019-12-18 v1.1.0-alpha.1: First alpha release using the new cc/v3, gocc, qbe toolchain. Some primitive tests pass on linux_{amd64,386}. Not yet safe for concurrent access by multiple goroutines. Next alpha release is planed to arrive before the end of this year.
2017-06-10 Windows/Intel no more uses the VM (thanks Steffen Butzer).
2017-06-05 Linux/Intel no more uses the VM (cznic/virtual).
Connecting to a database ¶
To access a Sqlite database do something like
import ( "database/sql" _ "modernc.org/sqlite" ) ... db, err := sql.Open("sqlite", dsnURI) ...
Debug and development versions ¶
A comma separated list of options can be passed to `go generate` via the environment variable GO_GENERATE. Some useful options include for example:
-DSQLITE_DEBUG -DSQLITE_MEM_DEBUG -ccgo-verify-structs
To create a debug/development version, issue for example:
$ GO_GENERATE=-DSQLITE_DEBUG,-DSQLITE_MEM_DEBUG go generate
Note: To run `go generate` you need to have modernc.org/ccgo/v3 installed.
Hacking ¶
This is an example of how to use the debug logs in modernc.org/libc when hunting a bug.
0:jnml@e5-1650:~/src/modernc.org/sqlite$ git status On branch master Your branch is up to date with 'origin/master'. nothing to commit, working tree clean 0:jnml@e5-1650:~/src/modernc.org/sqlite$ git log -1 commit df33b8d15107f3cc777799c0fe105f74ef499e62 (HEAD -> master, tag: v1.21.1, origin/master, origin/HEAD, wips, ok) Author: Jan Mercl <0xjnml@gmail.com> Date: Mon Mar 27 16:18:28 2023 +0200 upgrade to SQLite 3.41.2 0:jnml@e5-1650:~/src/modernc.org/sqlite$ rm -f /tmp/libc.log ; go test -v -tags=libc.dmesg -run TestScalar ; ls -l /tmp/libc.log test binary compiled for linux/amd64 === RUN TestScalar --- PASS: TestScalar (0.09s) PASS ok modernc.org/sqlite 0.128s -rw-r--r-- 1 jnml jnml 76 Apr 6 11:22 /tmp/libc.log 0:jnml@e5-1650:~/src/modernc.org/sqlite$ cat /tmp/libc.log [10723 sqlite.test] 2023-04-06 11:22:48.288066057 +0200 CEST m=+0.000707150 0:jnml@e5-1650:~/src/modernc.org/sqlite$
The /tmp/libc.log file is created as requested. No useful messages there because none are enabled in libc. Let's try to enable Xwrite as an example.
0:jnml@e5-1650:~/src/modernc.org/libc$ git status On branch master Your branch is up to date with 'origin/master'. Changes not staged for commit: (use "git add <file>..." to update what will be committed) (use "git restore <file>..." to discard changes in working directory) modified: libc_linux.go no changes added to commit (use "git add" and/or "git commit -a") 0:jnml@e5-1650:~/src/modernc.org/libc$ git log -1 commit 1e22c18cf2de8aa86d5b19b165f354f99c70479c (HEAD -> master, tag: v1.22.3, origin/master, origin/HEAD) Author: Jan Mercl <0xjnml@gmail.com> Date: Wed Feb 22 20:27:45 2023 +0100 support sqlite 3.41 on linux targets 0:jnml@e5-1650:~/src/modernc.org/libc$ git diff diff --git a/libc_linux.go b/libc_linux.go index 1c2f482..ac1f08d 100644 --- a/libc_linux.go +++ b/libc_linux.go @@ -332,19 +332,19 @@ func Xwrite(t *TLS, fd int32, buf uintptr, count types.Size_t) types.Ssize_t { var n uintptr switch n, _, err = unix.Syscall(unix.SYS_WRITE, uintptr(fd), buf, uintptr(count)); err { case 0: - // if dmesgs { - // // dmesg("%v: %d %#x: %#x\n%s", origin(1), fd, count, n, hex.Dump(GoBytes(buf, int(n)))) - // dmesg("%v: %d %#x: %#x", origin(1), fd, count, n) - // } + if dmesgs { + // dmesg("%v: %d %#x: %#x\n%s", origin(1), fd, count, n, hex.Dump(GoBytes(buf, int(n)))) + dmesg("%v: %d %#x: %#x", origin(1), fd, count, n) + } return types.Ssize_t(n) case errno.EAGAIN: // nop } } - // if dmesgs { - // dmesg("%v: fd %v, count %#x: %v", origin(1), fd, count, err) - // } + if dmesgs { + dmesg("%v: fd %v, count %#x: %v", origin(1), fd, count, err) + } t.setErrno(err) return -1 } 0:jnml@e5-1650:~/src/modernc.org/libc$
We need to tell the Go build system to use our local, patched/debug libc:
0:jnml@e5-1650:~/src/modernc.org/sqlite$ go work use $(go env GOPATH)/src/modernc.org/libc 0:jnml@e5-1650:~/src/modernc.org/sqlite$ go work use .
And run the test again:
0:jnml@e5-1650:~/src/modernc.org/sqlite$ rm -f /tmp/libc.log ; go test -v -tags=libc.dmesg -run TestScalar ; ls -l /tmp/libc.log test binary compiled for linux/amd64 === RUN TestScalar --- PASS: TestScalar (0.26s) PASS ok modernc.org/sqlite 0.285s -rw-r--r-- 1 jnml jnml 918 Apr 6 11:29 /tmp/libc.log 0:jnml@e5-1650:~/src/modernc.org/sqlite$ cat /tmp/libc.log [11910 sqlite.test] 2023-04-06 11:29:13.143589542 +0200 CEST m=+0.000689270 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0x200: 0x200 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0xc: 0xc [11910 sqlite.test] libc_linux.go:337:Xwrite: 7 0x1000: 0x1000 [11910 sqlite.test] libc_linux.go:337:Xwrite: 7 0x1000: 0x1000 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0x200: 0x200 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0x4: 0x4 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0x1000: 0x1000 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0x4: 0x4 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0x4: 0x4 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0x1000: 0x1000 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0x4: 0x4 [11910 sqlite.test] libc_linux.go:337:Xwrite: 8 0xc: 0xc [11910 sqlite.test] libc_linux.go:337:Xwrite: 7 0x1000: 0x1000 [11910 sqlite.test] libc_linux.go:337:Xwrite: 7 0x1000: 0x1000 0:jnml@e5-1650:~/src/modernc.org/sqlite$
Sqlite documentation ¶
Index ¶
- Variables
- func Limit(c *sql.Conn, id int, newVal int) (r int, err error)
- func MustRegisterCollationUtf8(zName string, impl func(left, right string) int)
- func MustRegisterDeterministicScalarFunction(zFuncName string, nArg int32, ...)
- func MustRegisterFunction(zFuncName string, impl *FunctionImpl)
- func MustRegisterScalarFunction(zFuncName string, nArg int32, ...)
- func RegisterCollationUtf8(zName string, impl func(left, right string) int) error
- func RegisterDeterministicScalarFunction(zFuncName string, nArg int32, ...) (err error)
- func RegisterFunction(zFuncName string, impl *FunctionImpl) error
- func RegisterScalarFunction(zFuncName string, nArg int32, ...) (err error)
- type AggregateFunction
- type Backup
- type Driver
- type Error
- type FunctionContext
- type FunctionImpl
Constants ¶
This section is empty.
Variables ¶
var ( // ErrorCodeString maps Error.Code() to its string representation. ErrorCodeString = map[int]string{ sqlite3.SQLITE_ABORT: "Callback routine requested an abort (SQLITE_ABORT)", sqlite3.SQLITE_AUTH: "Authorization denied (SQLITE_AUTH)", sqlite3.SQLITE_BUSY: "The database file is locked (SQLITE_BUSY)", sqlite3.SQLITE_CANTOPEN: "Unable to open the database file (SQLITE_CANTOPEN)", sqlite3.SQLITE_CONSTRAINT: "Abort due to constraint violation (SQLITE_CONSTRAINT)", sqlite3.SQLITE_CORRUPT: "The database disk image is malformed (SQLITE_CORRUPT)", sqlite3.SQLITE_DONE: "sqlite3_step() has finished executing (SQLITE_DONE)", sqlite3.SQLITE_EMPTY: "Internal use only (SQLITE_EMPTY)", sqlite3.SQLITE_ERROR: "Generic error (SQLITE_ERROR)", sqlite3.SQLITE_FORMAT: "Not used (SQLITE_FORMAT)", sqlite3.SQLITE_FULL: "Insertion failed because database is full (SQLITE_FULL)", sqlite3.SQLITE_INTERNAL: "Internal logic error in SQLite (SQLITE_INTERNAL)", sqlite3.SQLITE_INTERRUPT: "Operation terminated by sqlite3_interrupt()(SQLITE_INTERRUPT)", sqlite3.SQLITE_IOERR | (1 << 8): "(SQLITE_IOERR_READ)", sqlite3.SQLITE_IOERR | (10 << 8): "(SQLITE_IOERR_DELETE)", sqlite3.SQLITE_IOERR | (11 << 8): "(SQLITE_IOERR_BLOCKED)", sqlite3.SQLITE_IOERR | (12 << 8): "(SQLITE_IOERR_NOMEM)", sqlite3.SQLITE_IOERR | (13 << 8): "(SQLITE_IOERR_ACCESS)", sqlite3.SQLITE_IOERR | (14 << 8): "(SQLITE_IOERR_CHECKRESERVEDLOCK)", sqlite3.SQLITE_IOERR | (15 << 8): "(SQLITE_IOERR_LOCK)", sqlite3.SQLITE_IOERR | (16 << 8): "(SQLITE_IOERR_CLOSE)", sqlite3.SQLITE_IOERR | (17 << 8): "(SQLITE_IOERR_DIR_CLOSE)", sqlite3.SQLITE_IOERR | (2 << 8): "(SQLITE_IOERR_SHORT_READ)", sqlite3.SQLITE_IOERR | (3 << 8): "(SQLITE_IOERR_WRITE)", sqlite3.SQLITE_IOERR | (4 << 8): "(SQLITE_IOERR_FSYNC)", sqlite3.SQLITE_IOERR | (5 << 8): "(SQLITE_IOERR_DIR_FSYNC)", sqlite3.SQLITE_IOERR | (6 << 8): "(SQLITE_IOERR_TRUNCATE)", sqlite3.SQLITE_IOERR | (7 << 8): "(SQLITE_IOERR_FSTAT)", sqlite3.SQLITE_IOERR | (8 << 8): "(SQLITE_IOERR_UNLOCK)", sqlite3.SQLITE_IOERR | (9 << 8): "(SQLITE_IOERR_RDLOCK)", sqlite3.SQLITE_IOERR: "Some kind of disk I/O error occurred (SQLITE_IOERR)", sqlite3.SQLITE_LOCKED | (1 << 8): "(SQLITE_LOCKED_SHAREDCACHE)", sqlite3.SQLITE_LOCKED: "A table in the database is locked (SQLITE_LOCKED)", sqlite3.SQLITE_MISMATCH: "Data type mismatch (SQLITE_MISMATCH)", sqlite3.SQLITE_MISUSE: "Library used incorrectly (SQLITE_MISUSE)", sqlite3.SQLITE_NOLFS: "Uses OS features not supported on host (SQLITE_NOLFS)", sqlite3.SQLITE_NOMEM: "A malloc() failed (SQLITE_NOMEM)", sqlite3.SQLITE_NOTADB: "File opened that is not a database file (SQLITE_NOTADB)", sqlite3.SQLITE_NOTFOUND: "Unknown opcode in sqlite3_file_control() (SQLITE_NOTFOUND)", sqlite3.SQLITE_NOTICE: "Notifications from sqlite3_log() (SQLITE_NOTICE)", sqlite3.SQLITE_PERM: "Access permission denied (SQLITE_PERM)", sqlite3.SQLITE_PROTOCOL: "Database lock protocol error (SQLITE_PROTOCOL)", sqlite3.SQLITE_RANGE: "2nd parameter to sqlite3_bind out of range (SQLITE_RANGE)", sqlite3.SQLITE_READONLY: "Attempt to write a readonly database (SQLITE_READONLY)", sqlite3.SQLITE_ROW: "sqlite3_step() has another row ready (SQLITE_ROW)", sqlite3.SQLITE_SCHEMA: "The database schema changed (SQLITE_SCHEMA)", sqlite3.SQLITE_TOOBIG: "String or BLOB exceeds size limit (SQLITE_TOOBIG)", sqlite3.SQLITE_WARNING: "Warnings from sqlite3_log() (SQLITE_WARNING)", } )
Functions ¶
func Limit ¶ added in v1.23.1
Limit calls sqlite3_limit, see the docs at https://www.sqlite.org/c3ref/limit.html for details.
To get a sql.Conn from a *sql.DB, use (*sql.DB).Conn(). Limits are bound to the particular instance of 'c', so getting a new connection only to pass it to Limit is possibly not useful above querying what are the various configured default values.
func MustRegisterCollationUtf8 ¶ added in v1.26.0
MustRegisterCollationUtf8 is like RegisterCollationUtf8 but panics on error.
func MustRegisterDeterministicScalarFunction ¶ added in v1.16.0
func MustRegisterDeterministicScalarFunction( zFuncName string, nArg int32, xFunc func(ctx *FunctionContext, args []driver.Value) (driver.Value, error), )
MustRegisterDeterministicScalarFunction is like RegisterDeterministicScalarFunction but panics on error.
func MustRegisterFunction ¶ added in v1.23.0
func MustRegisterFunction( zFuncName string, impl *FunctionImpl, )
MustRegisterFunction is like RegisterFunction but panics on error.
func MustRegisterScalarFunction ¶ added in v1.16.0
func MustRegisterScalarFunction( zFuncName string, nArg int32, xFunc func(ctx *FunctionContext, args []driver.Value) (driver.Value, error), )
MustRegisterScalarFunction is like RegisterScalarFunction but panics on error.
func RegisterCollationUtf8 ¶ added in v1.26.0
RegisterCollationUtf8 makes a Go function available as a collation named zName. impl receives two UTF-8 strings: left and right. The result needs to be:
- 0 if left == right - 1 if left < right - +1 if left > right
impl must always return the same result given the same inputs. Additionally, it must have the following properties for all strings A, B and C: - if A==B, then B==A - if A==B and B==C, then A==C - if A<B, then B>A - if A<B and B<C, then A<C.
The new collation will be available to all new connections opened after executing RegisterCollationUtf8.
func RegisterDeterministicScalarFunction ¶ added in v1.16.0
func RegisterDeterministicScalarFunction( zFuncName string, nArg int32, xFunc func(ctx *FunctionContext, args []driver.Value) (driver.Value, error), ) (err error)
RegisterDeterministicScalarFunction registers a deterministic scalar function named zFuncName with nArg arguments. Passing -1 for nArg indicates the function is variadic. A deterministic function means that the function always gives the same output when the input parameters are the same.
The new function will be available to all new connections opened after executing RegisterDeterministicScalarFunction.
func RegisterFunction ¶ added in v1.23.0
func RegisterFunction( zFuncName string, impl *FunctionImpl, ) error
RegisterFunction registers a function named zFuncName with nArg arguments. Passing -1 for nArg indicates the function is variadic. The FunctionImpl determines whether the function is deterministic or not, and whether it is a scalar function (when Scalar is defined) or an aggregate function (when Scalar is not defined and MakeAggregate is defined).
The new function will be available to all new connections opened after executing RegisterFunction.
func RegisterScalarFunction ¶ added in v1.16.0
func RegisterScalarFunction( zFuncName string, nArg int32, xFunc func(ctx *FunctionContext, args []driver.Value) (driver.Value, error), ) (err error)
RegisterScalarFunction registers a scalar function named zFuncName with nArg arguments. Passing -1 for nArg indicates the function is variadic.
The new function will be available to all new connections opened after executing RegisterScalarFunction.
Types ¶
type AggregateFunction ¶ added in v1.23.0
type AggregateFunction interface { // Step is called for each row of an aggregate function's SQL // invocation. The argument Values are not valid past the return of the // function. Step(ctx *FunctionContext, rowArgs []driver.Value) error // WindowInverse is called to remove the oldest presently aggregated // result of Step from the current window. The arguments are those // passed to Step for the row being removed. The argument Values are not // valid past the return of the function. WindowInverse(ctx *FunctionContext, rowArgs []driver.Value) error // WindowValue is called to get the current value of an aggregate // function. This is used to return the final value of the function, // whether it is used as a window function or not. WindowValue(ctx *FunctionContext) (driver.Value, error) // Final is called after all of the aggregate function's input rows have // been stepped through. No other methods will be called on the // AggregateFunction after calling Final. WindowValue returns the value // from the function. Final(ctx *FunctionContext) }
An AggregateFunction is an invocation of an aggregate or window function. See the documentation for aggregate function callbacks and application-defined window functions for an overview.
type Backup ¶ added in v1.24.0
type Backup struct {
// contains filtered or unexported fields
}
Backup object is used to manage progress and cleanup an online backup. It is returned by NewBackup or NewRestore.
func (*Backup) Finish ¶ added in v1.24.0
Finish releases all resources associated with the Backup object. The Backup object is invalid and may not be used following a call to Finish.
func (*Backup) Step ¶ added in v1.24.0
Step will copy up to n pages between the source and destination databases specified by the backup object. If n is negative, all remaining source pages are copied. If it successfully copies n pages and there are still more pages to be copied, then the function returns true with no error. If it successfully finishes copying all pages from source to destination, then it returns false with no error. If an error occurs while running, then an error is returned.
type Driver ¶
type Driver struct {
// contains filtered or unexported fields
}
Driver implements database/sql/driver.Driver.
func (*Driver) Open ¶
Open returns a new connection to the database. The name is a string in a driver-specific format.
Open may return a cached connection (one previously closed), but doing so is unnecessary; the sql package maintains a pool of idle connections for efficient re-use.
The returned connection is only used by one goroutine at a time.
The name may be a filename, e.g., "/tmp/mydata.sqlite", or a URI, in which case it may include a '?' followed by one or more query parameters. For example, "file:///tmp/mydata.sqlite?_pragma=foreign_keys(1)&_time_format=sqlite". The supported query parameters are:
_pragma: Each value will be run as a "PRAGMA ..." statement (with the PRAGMA keyword added for you). May be specified more than once, '&'-separated. For more information on supported PRAGMAs see: https://www.sqlite.org/pragma.html
_time_format: The name of a format to use when writing time values to the database. Currently the only supported value is "sqlite", which corresponds to format 7 from https://www.sqlite.org/lang_datefunc.html#time_values, including the timezone specifier. If this parameter is not specified, then the default String() format will be used.
_txlock: The locking behavior to use when beginning a transaction. May be "deferred" (the default), "immediate", or "exclusive" (case insensitive). See: https://www.sqlite.org/lang_transaction.html#deferred_immediate_and_exclusive_transactions
type Error ¶ added in v1.3.0
type Error struct {
// contains filtered or unexported fields
}
Error represents sqlite library error code.
type FunctionContext ¶ added in v1.16.0
type FunctionContext struct {
// contains filtered or unexported fields
}
FunctionContext represents the context user defined functions execute in. Fields and/or methods of this type may get addedd in the future.
type FunctionImpl ¶ added in v1.23.0
type FunctionImpl struct { // NArgs is the required number of arguments that the function accepts. // If NArgs is negative, then the function is variadic. NArgs int32 // If Deterministic is true, the function must always give the same // output when the input parameters are the same. This enables functions // to be used in additional contexts like the WHERE clause of partial // indexes and enables additional optimizations. // // See https://sqlite.org/c3ref/c_deterministic.html#sqlitedeterministic // for more details. Deterministic bool // Scalar is called when a scalar function is invoked in SQL. The // argument Values are not valid past the return of the function. Scalar func(ctx *FunctionContext, args []driver.Value) (driver.Value, error) // MakeAggregate is called at the beginning of each evaluation of an // aggregate function. MakeAggregate func(ctx FunctionContext) (AggregateFunction, error) }
FunctionImpl describes an application-defined SQL function. If Scalar is set, it is treated as a scalar function; otherwise, it is treated as an aggregate function using MakeAggregate.