go-sqlite3-hak5/doc.go

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2014-07-04 00:54:28 +00:00
/*
Package sqlite3 provides interface to SQLite3 databases.
This works as driver for database/sql.
Installation
go get github.com/mattn/go-sqlite3
Supported Types
Currently, go-sqlite3 support 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 a
extension for 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 need to build as so/dll shared library. And you need to register
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 codes when connection established. database/sql
doesn't provide the way to get native go-sqlite3 interfaces. So if you want,
you need to hook ConnectHook and get the SQLiteConn.
sql.Register("sqlite3_with_hook_example",
&sqlite3.SQLiteDriver{
ConnectHook: func(conn *sqlite3.SQLiteConn) error {
sqlite3conn = append(sqlite3conn, conn)
return nil
},
})
*/
package sqlite3