A really GC-friendly MySQL package for Go

• Go 1.2 or higher
• MySQL (4.1+), MariaDB, Percona Server, Google CloudSQL or Sphinx (2.2.3+)

Simple install the package to your $GOPATH with the go tool from shell:

$ go get github.com/julienschmidt/gmysql

Make sure Git is installed on your machine and in your system's PATH.

The Data Source Name has a common format, like e.g. PEAR DB uses it, but without type-prefix (optional parts marked by squared brackets):

[username[:password]@][protocol[(address)]]/dbname[?param1=value1&...&paramN=valueN]

A DSN in its fullest form:

username:password@protocol(address)/dbname?param=value

Except for the databasename, all values are optional. So the minimal DSN is:

/dbname

If you do not want to preselect a database, leave dbname empty:

/

This has the same effect as an empty DSN string:

Passwords can consist of any character. Escaping is not necessary.

See net.Dial for more information which networks are available. In general you should use an Unix domain socket if available and TCP otherwise for best performance.

For TCP and UDP networks, addresses have the form host:port. If host is a literal IPv6 address, it must be enclosed in square brackets. The functions net.JoinHostPort and net.SplitHostPort manipulate addresses in this form.

For Unix domain sockets the address is the absolute path to the MySQL-Server-socket, e.g. /var/run/mysqld/mysqld.sock or /tmp/mysql.sock.

Parameters are case-sensitive!

Notice that any of true, TRUE, True or 1 is accepted to stand for a true boolean value. Not surprisingly, false can be specified as any of: false, FALSE, False or 0.

Type:           bool
Valid Values:   true, false
Default:        false

allowAllFiles=true disables the file Whitelist for LOAD DATA LOCAL INFILE and allows all files. Might be insecure!

Type:           bool
Valid Values:   true, false
Default:        false

allowCleartextPasswords=true allows using the cleartext client side plugin if required by an account, such as one defined with the PAM authentication plugin. Sending passwords in clear text may be a security problem in some configurations. To avoid problems if there is any possibility that the password would be intercepted, clients should connect to MySQL Server using a method that protects the password. Possibilities include TLS / SSL, IPsec, or a private network.

Type:           bool
Valid Values:   true, false
Default:        false

allowOldPasswords=true allows the usage of the insecure old password method. This should be avoided, but is necessary in some cases. See also the old_passwords wiki page.

Type:           string
Valid Values:   <name>
Default:        none

Sets the charset used for client-server interaction ("SET NAMES <value>"). If multiple charsets are set (separated by a comma), the following charset is used if setting the charset failes. This enables for example support for utf8mb4 (introduced in MySQL 5.5.3) with fallback to utf8 for older servers (charset=utf8mb4,utf8).

Usage of the charset parameter is discouraged because it issues additional queries to the server. Unless you need the fallback behavior, please use collation instead.

Type:           string
Valid Values:   <name>
Default:        utf8_general_ci

Sets the collation used for client-server interaction on connection. In contrast to charset, collation does not issue additional queries. If the specified collation is unavailable on the target server, the connection will fail.

A list of valid charsets for a server is retrievable with SHOW COLLATION.

Type:           bool
Valid Values:   true, false
Default:        false

clientFoundRows=true causes an UPDATE to return the number of matching rows instead of the number of rows changed.

Type:           bool
Valid Values:   true, false
Default:        false

When columnsWithAlias is true, calls to sql.Rows.Columns() will return the table alias and the column name separated by a dot. For example:

SELECT u.id FROM users as u

will return u.id instead of just id if columnsWithAlias=true.

Type:           string
Valid Values:   <escaped name>
Default:        UTC

Sets the location for time.Time values (when using parseTime=true). "Local" sets the system's location. See time.LoadLocation for details.

Note that this sets the location for time.Time values but does not change MySQL's time_zone setting. For that see the time_zone system variable, which can also be set as a DSN parameter.

Please keep in mind, that param values must be url.QueryEscape'ed. Alternatively you can manually replace the / with %2F. For example US/Pacific would be loc=US%2FPacific.

Type:           bool
Valid Values:   true, false
Default:        false

parseTime=true changes the output type of DATE and DATETIME values to time.Time instead of []byte / string

Type:           decimal number
Default:        0

I/O read timeout. The value must be a string of decimal numbers, each with optional fraction and a unit suffix ( "ms", "s", "m", "h" ), such as "30s", "0.5m" or "1m30s".

Type:           bool
Valid Values:   true, false
Default:        false

strict=true enables the strict mode in which MySQL warnings are treated as errors.

By default MySQL also treats notes as warnings. Use sql_notes=false to ignore notes. See the examples for an DSN example.

Type:           decimal number
Default:        OS default

Driver side connection timeout. The value must be a string of decimal numbers, each with optional fraction and a unit suffix ( "ms", "s", "m", "h" ), such as "30s", "0.5m" or "1m30s". To set a server side timeout, use the parameter wait_timeout.

Type:           bool / string
Valid Values:   true, false, skip-verify, <name>
Default:        false

tls=true enables TLS / SSL encrypted connection to the server. Use skip-verify if you want to use a self-signed or invalid certificate (server side). Use a custom value registered with mysql.RegisterTLSConfig.

Type:           decimal number
Default:        0

I/O write timeout. The value must be a string of decimal numbers, each with optional fraction and a unit suffix ( "ms", "s", "m", "h" ), such as "30s", "0.5m" or "1m30s".

All other parameters are interpreted as system variables:

• autocommit: "SET autocommit=<value>"
• time_zone: "SET time_zone=<value>"
• tx_isolation: "SET tx_isolation=<value>"
• param: "SET <param>=<value>"

The values must be url.QueryEscape'ed!

user@unix(/path/to/socket)/dbname

root:pw@unix(/tmp/mysql.sock)/myDatabase?loc=Local

user:password@tcp(localhost:5555)/dbname?tls=skip-verify&autocommit=true

Use the strict mode but ignore notes:

user:password@/dbname?strict=true&sql_notes=false

TCP via IPv6:

user:password@tcp([de:ad:be:ef::ca:fe]:80)/dbname?timeout=90s&collation=utf8mb4_unicode_ci

TCP on a remote host, e.g. Amazon RDS:

id:password@tcp(your-amazonaws-uri.com:3306)/dbname

Google Cloud SQL on App Engine:

user@cloudsql(project-id:instance-name)/dbname

TCP using default port (3306) on localhost:

user:password@tcp/dbname?charset=utf8mb4,utf8&sys_var=esc%40ped

Use the default protocol (tcp) and host (localhost:3306):

user:password@/dbname

No Database preselected:

user:password@/

Files must be whitelisted by registering them with mysql.RegisterLocalFile(filepath) (recommended) or the Whitelist check must be deactivated by using the DSN parameter allowAllFiles=true (Might be insecure!).

To use a io.Reader a handler function must be registered with mysql.RegisterReaderHandler(name, handler) which returns a io.Reader or io.ReadCloser. The Reader is available with the filepath Reader::<name> then. Choose different names for different handlers and DeregisterReaderHandler when you don't need it anymore.

See the godoc of gmysql for details.

The collation utf8_general_ci is used by default.

Other collations / charsets can be set using the collation DSN parameter.

Version 1.0 of the driver recommended adding &charset=utf8 (alias for SET NAMES utf8) to the DSN to enable proper UTF-8 support. This is not necessary anymore. The collation parameter should be preferred to set another collation / charset than the default.

See http://dev.mysql.com/doc/refman/5.7/en/charset-unicode.html for more details on MySQL's Unicode support.

gmysql is not feature-complete yet. Your help is very appreciated. If you want to contribute, you can work on an open issue or review a pull request.

See the Contribution Guidelines for details.

• conn.QueryRow / stmt.QueryRow
• proper type conversion
• RawBytes

gmysql is licensed under the Mozilla Public License Version 2.0

Mozilla summarizes the license scope as follows:

MPL: The copyleft applies to any files containing MPLed code.

That means:

• You can use the unchanged source code both in private and commercially
• When distributing, you must publish the source code of any changed files licensed under the MPL 2.0 under a) the MPL 2.0 itself or b) a compatible license (e.g. GPL 3.0 or Apache License 2.0)
• You needn't publish the source code of your library as long as the files licensed under the MPL 2.0 are unchanged

Please read the MPL 2.0 FAQ if you have further questions regarding the license.

You can read the full terms here: LICENSE