Added BigQuery database driver

Makefile

@@ -1,5 +1,5 @@
 SOURCE ?= file go_bindata github github_ee bitbucket aws_s3 google_cloud_storage godoc_vfs gitlab
-DATABASE ?= postgres mysql redshift cassandra spanner cockroachdb yugabytedb clickhouse mongodb sqlserver firebird neo4j pgx
+DATABASE ?= postgres mysql redshift cassandra spanner cockroachdb yugabytedb clickhouse mongodb sqlserver firebird neo4j pgx bigquery
 DATABASE_TEST ?= $(DATABASE) sqlite sqlite3 sqlcipher
 VERSION ?= $(shell git describe --tags 2>/dev/null | cut -c 2-)
 TEST_FLAGS ?=

README.md

@@ -42,6 +42,7 @@ Database drivers run migrations. [Add a new database?](database/driver.go)
 * [ClickHouse](database/clickhouse)
 * [Firebird](database/firebird)
 * [MS SQL Server](database/sqlserver)
+* [BigQuery (Beta)](database/bigquery)
 
 ### Database URLs
 

database/bigquery/.gitignore

@@ -0,0 +1,2 @@
+tmp/
+!tmp/.gitkeep

database/bigquery/README.md

@@ -0,0 +1,40 @@
+# BigQuery (Beta)
+
+* Driver works with Google Cloud BigQuery
+* [Examples](./examples)
+
+### Usage
+`bigquery://https://www.googleapis.com/bigquery/v2:443?x-migrations-table=schema_migrations&x-statement-timeout=0&credentials_filename=./myproject-XXXXXXXXXXXXX-XXXXXXXXXXXX.json&project_id=myproject-XXXXXXXXXXXXX&dataset_id=mydataset`
+
+
+### System variables reference
+https://cloud.google.com/bigquery/docs/reference/system-variables
+
+| Key                      | WithInstance Config | Default                  | Description                                                                                                                                                                                                                                                                                                                                                                                    |
+|--------------------------|---------------------|--------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| `x-migrations-table`     | `MigrationsTable`   | schema_migrations        | Name of the migrations table                                                                                                                                                                                                                                                                                                                                                                   |
+| `x-statement-timeout`    | `StatementTimeout`  | 0                        | Abort any statement that takes more than the specified number of milliseconds                                                                                                                                                                                                                                                                                                                  |
+| `credentials_filename`   | -                   | -                        | The location of a credential JSON file.                                                                                                                                                                                                                                                                                                                                                        |
+| `project_id`             | -                   | -                        | The current Google Cloud project ID.                                                                                                                                                                                                                                                                                                                                                           |
+| `dataset_id`             | `DatasetID`         | -                        | ID of the default dataset in the current project. This ID is used when a dataset is not specified for a project in the query. You can use the SET statement to assign @@dataset_id to another dataset ID in the current project. The system variables @@dataset_project_id and @@dataset_id can be set and used together.                                                                      |
+| `dataset_project_id`     | `DatasetProjectID`  | the same as `project_id` | ID of the default project that's used when one is not specified for a dataset used in the query. If @@dataset_project_id is not set, or if it is set to NULL, the query-executing project (@@project_id) is used. You can use the SET statement to assign @@dataset_project_id to another project ID. The system variables @@dataset_project_id and @@dataset_id can be set and used together. |
+| `query_label`            | `QueryLabel`        | NULL                     | Query label to associate with query jobs in the current multi-statement query or session. If set in a query, all subsequent query jobs in the script or session will have this label. If not set in a query, the value for this system variable is NULL. For an example of how to set this system variable, see Associate jobs in a session with a label.                                      |
+| `time_zone`              | `TimeZone`          | UTC                      | The default time zone to use in time zone-dependent SQL functions, when a time zone is not specified as an argument. @@time_zone can be modified by using a SET statement to any valid time zone name. At the start of each script, @@time_zone begins as “UTC”.                                                                                                                               |
+
+
+
+### Environment variables:
+- https://cloud.google.com/docs/authentication/application-default-credentials#GAC
+
+| Key                            | Description                                      |
+|--------------------------------|--------------------------------------------------|
+| GOOGLE_APPLICATION_CREDENTIALS | The location of a credential JSON file.          | 
+
+
+### Data definition language (DDL) statements in Google Standard SQL
+https://cloud.google.com/bigquery/docs/reference/standard-sql/data-definition-language
+
+
+### Work with multi-statement queries
+https://cloud.google.com/bigquery/docs/multi-statement-queries
+