| commit | 2c4130252260a6667288673e42f0a5dfe8e6c406 | [log] [tgz] |
|---|---|---|
| author | Kenneth Shaw <kenshaw@gmail.com> | Mon Oct 16 11:14:56 2017 +0700 |
| committer | Francis Chuang <francis.chuang@boostport.com> | Tue Oct 17 11:10:29 2017 +1100 |
| tree | c6bfcbe0bce0d9e3b06822e308878def2d26dd62 | |
| parent | cfc09cd32441e738799bc5d142d17c83b4aedd1e [diff] |
A number of fixes, as itemized: - Change import paths for github.com/jcmturner/gokrb5/* -> gopkg.in/jcmturner/gokrb5.v1/* - Update Gopkg.lock accordingly - Adding line end to files missing them - Reorder import list on class_mappings.go - Fix gen-protobuf.sh script and permissions - Generate latest message/*.pb.go files
An Apache Phoenix/Avatica driver for Go's database/sql package
Install using your dependency management tool (we recommend dep!):
$ dep ensure -add github.com/apache/calcite-avatica-go
The Phoenix/Avatica driver implements Go‘s database/sql/driver interface, so, import Go’s database/sql package and the driver:
import "database/sql"
import _ "github.com/apache/calcite-avatica-go"
db, err := sql.Open("avatica", "http://localhost:8765")
Then simply use the database connection to query some data, for example:
rows := db.Query("SELECT COUNT(*) FROM test")
The DSN has the following format (optional parts are marked by square brackets):
http://[username:password@]address:port[/schema][?parameter1=value&...parameterN=value]
In other words, the scheme (http), address and port is mandatory, but the schema and parameters are optional.
This is the JDBC username that is passed directly to the backing database. It is NOT used for authenticating against Avatica.
This is the JDBC password that is passed directly to the backing database. It is NOT used for authenticating against Avatica.
The schema path sets the default schema to use for this connection. For example, if you set it to myschema, then executing the query SELECT * FROM my_table will have the equivalence of SELECT * FROM myschema.my_table. If schema is set, you can still work on tables in other schemas by supplying a schema prefix: SELECT * FROM myotherschema.my_other_table.
The following parameters are supported:
The authentication type to use when authenticating against Avatica. Valid values are BASIC for HTTP Basic authentication, DIGEST for HTTP Digest authentication, and SPNEGO for Kerberos with SPNEGO authentication.
The user to use when authenticating against Avatica. This parameter is required if authentication is BASIC or DIGEST.
The password to use when authenticating against Avatica. This parameter is required if authentication is BASIC or DIGEST.
The Kerberos principal to use when authenticating against Avatica. It should be in the form primary/instance@realm, where the instance is optional. This parameter is required if authentication is SPNEGO and you want the driver to perform the Kerberos login.
The path to the Kerberos keytab to use when authenticating against Avatica. This parameter is required if authentication is SPNEGO and you want the driver to perform the Kerberos login.
The path to the Kerberos configuration to use when authenticating against Avatica. This parameter is required if authentication is SPNEGO and you want the driver to perform the Kerberos login.
The path to the Kerberos credential cache file to use when authenticating against Avatica. This parameter is required if authentication is SPNEGO and you have logged into Kerberos already and want the driver to use the existing credentials.
The location will be set as the location of unserialized time.Time values. It must be a valid timezone. If you want to use the local timezone, use Local. By default, this is set to UTC.
The maxRowsTotal parameter sets the maximum number of rows to return for a given query. By default, this is set to -1, so that there is no limit on the number of rows returned.
The frameMaxSize parameter sets the maximum number of rows to return in a frame. Depending on the number of rows returned and subject to the limits of maxRowsTotal, a query result set can contain rows in multiple frames. These additional frames are then fetched on a as-needed basis. frameMaxSize allows you to control the number of rows in each frame to suit your application's performance profile. By default this is set to -1, so that there is no limit on the number of rows in a frame.
Setting transactionIsolation allows you to set the isolation level for transactions using the connection. The value should be a positive integer analogous to the transaction levels defined by the JDBC specification. The default value is 0, which means transactions are not supported. This is to deal with the fact that Calcite/Avatica works with many types of backends, with some backends having no transaction support. If you are using Apache Phoenix 4.7 onwards, we recommend setting it to 4, which is the maximum isolation level supported.
The supported values for transactionIsolation are:
| Value | JDBC Constant | Description |
|---|---|---|
| 0 | none | Transactions are not supported |
| 1 | TRANSACTION_READ_UNCOMMITTED | Dirty reads, non-repeatable reads and phantom reads may occur. |
| 2 | TRANSACTION_READ_COMMITTED | Dirty reads are prevented, but non-repeatable reads and phantom reads may occur. |
| 4 | TRANSACTION_REPEATABLE_READ | Dirty reads and non-repeatable reads are prevented, but phantom reads may occur. |
| 8 | TRANSACTION_SERIALIZABLE | Dirty reads, non-repeatable reads, and phantom reads are all prevented. |
The following Phoenix/Avatica datatypes are automatically converted to and from time.Time: TIME, DATE and TIMESTAMP.
It is important to understand that avatica and the underlying database ignores the timezone. If you save a time.Time to the database, the timezone is ignored and vice-versa. This is why you need to make sure the location parameter in your DSN is set to the same value as the location of the time.Time values you are inserting into the database.
We recommend using UTC, which is the default value of location.
| Driver Version | Phoenix Version | Calcite-Avatica Version |
|---|---|---|
| 1.x.x | >= 4.8.0 | >= 1.8.0 |
| 2.x.x | >= 4.8.0 | >= 1.8.0 |
To run tests, but skip tests in the vendor directory (to avoid running tests for the dependencies), run:
go test $(go list ./... | grep -v /vendor/)
To update the procotol buffer definitions, update CALCITE_VER in gen-protobuf.bat and gen-protobuf.sh to match the version included by Phoenix and then run the appropriate script for your platform.
The driver is licensed under the Apache 2 license. See the LICENSE and NOTICE files for more information.