hammer is a command-line tool to schema management for Google Cloud Spanner.
Download the single-binary executable from:
https://github.com/daichirata/hammer/releases
or
$ go get -u github.com/daichirata/hammer$ hammer -h
hammer is a command-line tool to schema management for Google Cloud Spanner.
Usage:
hammer [command]
Examples:
* Export spanner schema
hammer export spanner://projects/projectId/instances/instanceId/databases/databaseName > schema.sql
* Apply local schema file
hammer apply spanner://projects/projectId/instances/instanceId/databases/databaseName /path/to/file
* Create database and apply local schema (faster than running database creation and schema apply separately)
hammer create spanner://projects/projectId/instances/instanceId/databases/databaseName /path/to/file
* Copy database
hammer create spanner://projects/projectId/instances/instanceId/databases/databaseName1 spanner://projects/projectId/instances/instanceId/databases/databaseName2
* Compare local files
hammer diff /path/to/file /another/path/to/file
* Compare local file against spanner schema
hammer diff /path/to/file spanner://projects/projectId/instances/instanceId/databases/databaseName
* Compare spanner schema against spanner schema
hammer diff spanner://projects/projectId/instances/instanceId/databases/databaseName1 spanner://projects/projectId/instances/instanceId/databases/databaseName2
Available Commands:
apply Apply schema
create Create database and apply schema
diff Diff schema
export Export schema
help Help about any command
Flags:
-h, --help help for hammer
Use "hammer [command] --help" for more information about a command.
The DSN must be given in the following format.
spanner://projects/{projectId}/instances/{instanceId}/databases/{databaseName}?credentials=/path/to/file.json
| Param | Required | Description |
|---|---|---|
projectId |
true | The Google Cloud Platform project id |
instanceId |
true | The id of the instance running Spanner |
databaseName |
true | The name of the Spanner database |
credentials |
false | The path to the keyfile. If not present, client will use your default application credentials. |
Suppose you have an existing SQL schema like the following:
CREATE TABLE users (
user_id STRING(36) NOT NULL,
) PRIMARY KEY(user_id);And you want "upgrade" your schema to the following:
CREATE TABLE users (
user_id STRING(36) NOT NULL,
age INT64,
name STRING(MAX) NOT NULL,
) PRIMARY KEY(user_id);
CREATE INDEX idx_users_name ON users (name);Hammer changes the schema by applying the following SQL to the spanner:
hammer diff old.sql new.sql
ALTER TABLE users ADD COLUMN age INT64
ALTER TABLE users ADD COLUMN name STRING(MAX)
UPDATE users SET name = '' WHERE name IS NULL
ALTER TABLE users ALTER COLUMN name STRING(MAX) NOT NULL
CREATE INDEX idx_users_name ON users(name)When adding a column with the NOT NULL attribute, update the default value after adding the column once, and then add the NOT NULL attribute.
Unless otherwise noted, the hammer source files are distributed under the MIT License found in the LICENSE file.