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Diffstat (limited to 'dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.22/doc.go')
-rw-r--r-- | dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.22/doc.go | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.22/doc.go b/dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.22/doc.go new file mode 100644 index 0000000..a3bcebb --- /dev/null +++ b/dependencies/pkg/mod/github.com/mattn/go-sqlite3@v1.14.22/doc.go @@ -0,0 +1,134 @@ +/* +Package sqlite3 provides interface to SQLite3 databases. + +This works as a driver for database/sql. + +Installation + + go get github.com/mattn/go-sqlite3 + +# Supported Types + +Currently, go-sqlite3 supports the following data types. + + +------------------------------+ + |go | sqlite3 | + |----------|-------------------| + |nil | null | + |int | integer | + |int64 | integer | + |float64 | float | + |bool | integer | + |[]byte | blob | + |string | text | + |time.Time | timestamp/datetime| + +------------------------------+ + +# SQLite3 Extension + +You can write your own extension module for sqlite3. For example, below is an +extension for a Regexp matcher operation. + + #include <pcre.h> + #include <string.h> + #include <stdio.h> + #include <sqlite3ext.h> + + SQLITE_EXTENSION_INIT1 + static void regexp_func(sqlite3_context *context, int argc, sqlite3_value **argv) { + if (argc >= 2) { + const char *target = (const char *)sqlite3_value_text(argv[1]); + const char *pattern = (const char *)sqlite3_value_text(argv[0]); + const char* errstr = NULL; + int erroff = 0; + int vec[500]; + int n, rc; + pcre* re = pcre_compile(pattern, 0, &errstr, &erroff, NULL); + rc = pcre_exec(re, NULL, target, strlen(target), 0, 0, vec, 500); + if (rc <= 0) { + sqlite3_result_error(context, errstr, 0); + return; + } + sqlite3_result_int(context, 1); + } + } + + #ifdef _WIN32 + __declspec(dllexport) + #endif + int sqlite3_extension_init(sqlite3 *db, char **errmsg, + const sqlite3_api_routines *api) { + SQLITE_EXTENSION_INIT2(api); + return sqlite3_create_function(db, "regexp", 2, SQLITE_UTF8, + (void*)db, regexp_func, NULL, NULL); + } + +It needs to be built as a so/dll shared library. And you need to register +the extension module like below. + + sql.Register("sqlite3_with_extensions", + &sqlite3.SQLiteDriver{ + Extensions: []string{ + "sqlite3_mod_regexp", + }, + }) + +Then, you can use this extension. + + rows, err := db.Query("select text from mytable where name regexp '^golang'") + +# Connection Hook + +You can hook and inject your code when the connection is established by setting +ConnectHook to get the SQLiteConn. + + sql.Register("sqlite3_with_hook_example", + &sqlite3.SQLiteDriver{ + ConnectHook: func(conn *sqlite3.SQLiteConn) error { + sqlite3conn = append(sqlite3conn, conn) + return nil + }, + }) + +You can also use database/sql.Conn.Raw (Go >= 1.13): + + conn, err := db.Conn(context.Background()) + // if err != nil { ... } + defer conn.Close() + err = conn.Raw(func (driverConn any) error { + sqliteConn := driverConn.(*sqlite3.SQLiteConn) + // ... use sqliteConn + }) + // if err != nil { ... } + +# Go SQlite3 Extensions + +If you want to register Go functions as SQLite extension functions +you can make a custom driver by calling RegisterFunction from +ConnectHook. + + regex = func(re, s string) (bool, error) { + return regexp.MatchString(re, s) + } + sql.Register("sqlite3_extended", + &sqlite3.SQLiteDriver{ + ConnectHook: func(conn *sqlite3.SQLiteConn) error { + return conn.RegisterFunc("regexp", regex, true) + }, + }) + +You can then use the custom driver by passing its name to sql.Open. + + var i int + conn, err := sql.Open("sqlite3_extended", "./foo.db") + if err != nil { + panic(err) + } + err = db.QueryRow(`SELECT regexp("foo.*", "seafood")`).Scan(&i) + if err != nil { + panic(err) + } + +See the documentation of RegisterFunc for more details. +*/ +package sqlite3 |