This package can be installed with the go get command:
go get github.com/mattn/go-sqlite3
go-sqlite3 is cgo package.
If you want to build your app using go-sqlite3, you need gcc.
However, after you have built and installed go-sqlite3 with go install github.com/mattn/go-sqlite3 (which requires gcc), you can build your app without relying on gcc in future.
Important: because this is a CGO enabled package, you are required to set the environment variable CGO_ENABLED=1 and have a gcc compile present within your path.
Examples can be found under the examples directory.
Connection String
When creating a new SQLite database or connection to an existing one, with the file name additional options can be given.
This is also known as a DSN (Data Source Name) string.
Options are append after the filename of the SQLite database.
The database filename and options are separated by an ? (Question Mark).
Options should be URL-encoded (see url.QueryEscape).
This also applies when using an in-memory database instead of a file.
Options can be given using the following format: KEYWORD=VALUE and multiple options can be combined with the & ampersand.
This library supports DSN options of SQLite itself and provides additional options.
When this pragma is on, the SQLITE_MASTER tables in which database can be changed using ordinary UPDATE, INSERT, and DELETE statements. Warning: misuse of this pragma can easily result in a corrupt database file.
This package allows additional configuration of features available within SQLite3 to be enabled or disabled by golang build constraints also known as build tags.
Click here for more information about build tags / constraints.
Usage
If you wish to build this library with additional extensions / features, use the following command:
go build --tags "<FEATURE>"
For available features, see the extension list.
When using multiple build tags, all the different tags should be space delimited.
Example:
go build --tags "icu json1 fts5 secure_delete"
Feature / Extension List
Extension
Build Tag
Description
Additional Statistics
sqlite_stat4
This option adds additional logic to the ANALYZE command and to the query planner that can help SQLite to chose a better query plan under certain situations. The ANALYZE command is enhanced to collect histogram data from all columns of every index and store that data in the sqlite_stat4 table.
The query planner will then use the histogram data to help it make better index choices. The downside of this compile-time option is that it violates the query planner stability guarantee making it more difficult to ensure consistent performance in mass-produced applications.
SQLITE_ENABLE_STAT4 is an enhancement of SQLITE_ENABLE_STAT3. STAT3 only recorded histogram data for the left-most column of each index whereas the STAT4 enhancement records histogram data from all columns of each index.
The SQLITE_ENABLE_STAT3 compile-time option is a no-op and is ignored if the SQLITE_ENABLE_STAT4 compile-time option is used
Allow URI Authority
sqlite_allow_uri_authority
URI filenames normally throws an error if the authority section is not either empty or "localhost".
However, if SQLite is compiled with the SQLITE_ALLOW_URI_AUTHORITY compile-time option, then the URI is converted into a Uniform Naming Convention (UNC) filename and passed down to the underlying operating system that way
App Armor
sqlite_app_armor
When defined, this C-preprocessor macro activates extra code that attempts to detect misuse of the SQLite API, such as passing in NULL pointers to required parameters or using objects after they have been destroyed.
App Armor is not available under Windows.
Disable Load Extensions
sqlite_omit_load_extension
Loading of external extensions is enabled by default.
To disable extension loading add the build tag sqlite_omit_load_extension.
Foreign Keys
sqlite_foreign_keys
This macro determines whether enforcement of foreign key constraints is enabled or disabled by default for new database connections.
Each database connection can always turn enforcement of foreign key constraints on and off and run-time using the foreign_keys pragma.
Enforcement of foreign key constraints is normally off by default, but if this compile-time parameter is set to 1, enforcement of foreign key constraints will be on by default
Full Auto Vacuum
sqlite_vacuum_full
Set the default auto vacuum to full
Incremental Auto Vacuum
sqlite_vacuum_incr
Set the default auto vacuum to incremental
Full Text Search Engine
sqlite_fts5
When this option is defined in the amalgamation, versions 5 of the full-text search engine (fts5) is added to the build automatically
International Components for Unicode
sqlite_icu
This option causes the International Components for Unicode or "ICU" extension to SQLite to be added to the build
Introspect PRAGMAS
sqlite_introspect
This option adds some extra PRAGMA statements.
PRAGMA function_list
PRAGMA module_list
PRAGMA pragma_list
JSON SQL Functions
sqlite_json
When this option is defined in the amalgamation, the JSON SQL functions are added to the build automatically
Pre Update Hook
sqlite_preupdate_hook
Registers a callback function that is invoked prior to each INSERT, UPDATE, and DELETE operation on a database table.
Secure Delete
sqlite_secure_delete
This compile-time option changes the default setting of the secure_delete pragma.
When this option is not used, secure_delete defaults to off. When this option is present, secure_delete defaults to on.
The secure_delete setting causes deleted content to be overwritten with zeros. There is a small performance penalty since additional I/O must occur.
On the other hand, secure_delete can prevent fragments of sensitive information from lingering in unused parts of the database file after it has been deleted. See the documentation on the secure_delete pragma for additional information
This package requires the CGO_ENABLED=1 ennvironment variable if not set by default, and the presence of the gcc compiler.
If you need to add additional CFLAGS or LDFLAGS to the build command, and do not want to modify this package, then this can be achieved by using the CGO_CFLAGS and CGO_LDFLAGS environment variables.
Android
This package can be compiled for android.
Compile with:
Probably, you are using go 1.0, go1.0 has a problem when it comes to compiling/linking on windows 64bit.
See: #27
go get github.com/mattn/go-sqlite3 throws compilation error.
gcc throws: internal compiler error
Remove the download repository from your disk and try re-install with:
go install github.com/mattn/go-sqlite3
User Authentication
This package supports the SQLite User Authentication module.
Compile
To use the User authentication module, the package has to be compiled with the tag sqlite_userauth. See Features.
Usage
Create protected database
To create a database protected by user authentication, provide the following argument to the connection string _auth.
This will enable user authentication within the database. This option however requires two additional arguments:
_auth_user
_auth_pass
When _auth is present in the connection string user authentication will be enabled and the provided user will be created
as an admin user. After initial creation, the parameter _auth has no effect anymore and can be omitted from the connection string.
Example connection strings:
Create an user authentication database with user admin and password admin:
The passwords within the user authentication module of SQLite are encoded with the SQLite function sqlite_cryp.
This function uses a ceasar-cypher which is quite insecure.
This library provides several additional password encoders which can be configured through the connection string.
The password cypher can be configured with the key _auth_crypt. And if the configured password encoder also requires an
salt this can be configured with _auth_salt.
Available Encoders
SHA1
SSHA1 (Salted SHA1)
SHA256
SSHA256 (salted SHA256)
SHA384
SSHA384 (salted SHA384)
SHA512
SSHA512 (salted SHA512)
Restrictions
Operations on the database regarding user management can only be preformed by an administrator user.
Support
The user authentication supports two kinds of users:
administrators
regular users
User Management
User management can be done by directly using the *SQLiteConn or by SQL.
SQL
The following sql functions are available for user management:
Function
Arguments
Description
authenticate
username string, password string
Will authenticate an user, this is done by the connection; and should not be used manually.
auth_user_add
username string, password string, admin int
This function will add an user to the database. if the database is not protected by user authentication it will enable it. Argument admin is an integer identifying if the added user should be an administrator. Only Administrators can add administrators.
auth_user_change
username string, password string, admin int
Function to modify an user. Users can change their own password, but only an administrator can change the administrator flag.
authUserDelete
username string
Delete an user from the database. Can only be used by an administrator. The current logged in administrator cannot be deleted. This is to make sure their is always an administrator remaining.
These functions will return an integer:
0 (SQLITE_OK)
23 (SQLITE_AUTH) Failed to perform due to authentication or insufficient privileges
Examples
// Autheticate user
// Create Admin User
SELECT auth_user_add('admin2', 'admin2', 1);
// Change password for user
SELECT auth_user_change('user', 'userpassword', 0);
//Delete user
SELECT user_delete('user');
*SQLiteConn
The following functions are available for User authentication from the *SQLiteConn:
Use _loc=auto in SQLite3 filename schema like file:foo.db?_loc=auto.
Can I use this in multiple routines concurrently?
Yes for readonly. But not for writable. See #50, #51, #209, #274.
Why I'm getting no such table error?
Why is it racy if I use a sql.Open("sqlite3", ":memory:") database?
Each connection to ":memory:" opens a brand new in-memory sql database, so if
the stdlib's sql engine happens to open another connection and you've only
specified ":memory:", that connection will see a brand new database. A
workaround is to use "file::memory:?cache=shared" (or "file:foobar?mode=memory&cache=shared"). Every
connection to this string will point to the same in-memory database.
Note that if the last database connection in the pool closes, the in-memory database is deleted. Make sure the max idle connection limit is > 0, and the connection lifetime is infinite.
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