Creating your first Tarantool database

Example on GitHub: create_db

In this tutorial, you create a Tarantool database, write data to it, and select data from this database.

Before starting this tutorial:

• Install the tt utility.

• Install Tarantool.

The tt create command can be used to create an application from a predefined or custom template. In this tutorial, the application layout is prepared manually:

1. Create a tt environment in the current directory using the tt init command.
2. Inside the instances.enabled directory of the created tt environment, create the create_db directory.
3. Inside instances.enabled/create_db, create the instances.yml and config.yaml files:
   • instances.yml specifies instances to run in the current environment. In this example, there is one instance:

 
instance001:

 
- `config.yaml` contains basic instance  [configuration](../../platform/configuration#configuration_file):

 
groups:  group001:    replicasets:      replicaset001:        instances:          instance001:            iproto:              listen:              - uri: '127.0.0.1:3301'

 
The instance in the configuration accepts incoming requests on the  `3301` port.

1. Start the Tarantool instance from the tt environment directory using tt start:

    
   $ tt start create_db

2. To check the running instance, use the tt status command:

    
   $ tt status create_dbINSTANCE               STATUS   PID   MODE  CONFIG  BOX      UPSTREAMcreate_db:instance001  RUNNING  8685  RW    ready   running  --

3. Connect to the instance with tt connect:

    
   $ tt connect create_db:instance001   • Connecting to the instance...   • Connected to create_db:instance001create_db:instance001>

   This command opens an interactive Tarantool console with the create_db:instance001> prompt. Now you can enter requests in the command line.

1. Create a space named bands:

    
   create_db:instance001> box.schema.space.create('bands')---- engine: memtx  before_replace: 'function: 0x010229d788'  field_count: 0  is_sync: false  is_local: false  on_replace: 'function: 0x010229d750'  temporary: false  index:   type: normal  enabled: false  name: bands  id: 512- created...

2. Format the created space by specifying field names and types:

    
   create_db:instance001> box.space.bands:format({                           { name = 'id', type = 'unsigned' },                           { name = 'band_name', type = 'string' },                           { name = 'year', type = 'unsigned' }                       })---...

1. Create the primary index based on the id field:

    
   create_db:instance001> box.space.bands:create_index('primary', { parts = { 'id' } })---- unique: true  parts:  - fieldno: 1    sort_order: asc    type: unsigned    exclude_null: false    is_nullable: false  hint: true  id: 0  type: TREE  space_id: 512  name: primary...

2. Create the secondary index based on the band_name field:

    
   create_db:instance001> box.space.bands:create_index('secondary', { parts = { 'band_name' } })---- unique: true  parts:  - fieldno: 2    sort_order: asc    type: string    exclude_null: false    is_nullable: false  hint: true  id: 1  type: TREE  space_id: 512  name: secondary...

1. Insert three tuples into the space:

    
   create_db:instance001> box.space.bands:insert { 1, 'Roxette', 1986 }---- [1, 'Roxette', 1986]...create_db:instance001> box.space.bands:insert { 2, 'Scorpions', 1965 }---- [2, 'Scorpions', 1965]...create_db:instance001> box.space.bands:insert { 3, 'Ace of Base', 1987 }---- [3, 'Ace of Base', 1987]...

2. Select a tuple using the primary index:

    
   create_db:instance001> box.space.bands:select { 3 }---- - [3, 'Ace of Base', 1987]...

3. Select tuples using the secondary index:

    
   create_db:instance001> box.space.bands.index.secondary:select{'Scorpions'}---- - [2, 'Scorpions', 1965]...