View definition

package sqlite3

Defined in github.com/mattn/go-sqlite3/.

Description

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. database/sql doesn't provide a way to get native go-sqlite3 interfaces. So if you want, you need to set 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
				},
		})

Go SQlite3 Extensions

If you want to register Go functions as SQLite extension functions, call RegisterFunction from ConnectHook.

regex = func(re, s string) (bool, error) {
	return regexp.MatchString(re, s)
}
sql.Register("sqlite3_with_go_func",
		&sqlite3.SQLiteDriver{
				ConnectHook: func(conn *sqlite3.SQLiteConn) error {
					return conn.RegisterFunc("regexp", regex, true)
				},
		})

See the documentation of RegisterFunc for more details.

sqlite3 is referenced in 56 repositories

github.com/mattn/go-sqlite3 github.com/google/certificate-transparency github.com/contactlab/CLABPush-Go

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