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Create a sample space named ``bands``:
bands = box.schema.space.create('bands')
Format the created space by specifying field names and types:
box.space.bands:format({
{ name = 'id', type = 'unsigned' },
{ name = 'band_name', type = 'string' },
{ name = 'year', type = 'unsigned' }
})
Create the **primary** index (named ``primary``):
box.space.bands:create_index('primary', { parts = { 'id' } })
This index is based on the ``id`` field of each tuple.
Insert some :ref:`tuples <index-box_tuple>` into the space:
box.space.bands:insert { 1, 'Roxette', 1986 }
box.space.bands:insert { 2, 'Scorpions', 1965 }
box.space.bands:insert { 3, 'Ace of Base', 1987 }
box.space.bands:insert { 4, 'The Beatles', 1960 }
box.space.bands:insert { 5, 'Pink Floyd', 1965 }
box.space.bands:insert { 6, 'The Rolling Stones', 1962 }
box.space.bands:insert { 7, 'The Doors', 1965 }
box.space.bands:insert { 8, 'Nirvana', 1987 }
box.space.bands:insert { 9, 'Led Zeppelin', 1968 }
box.space.bands:insert { 10, 'Queen', 1970 }
Create **secondary indexes**:
-- Create a unique secondary index --
box.space.bands:create_index('band', { parts = { 'band_name' } })

-- Create a non-unique secondary index --
box.space.bands:create_index('year', { parts = { { 'year' } }, unique = false })
Create a **multi-part index** with two parts:
box.space.bands:create_index('year_band', { parts = { { 'year' }, { 'band_name' } } })
There are the following SELECT variations:
The search can use **comparisons** other than equality:
-- Select maximum 3 tuples with the key value greater than 1965 --
select_greater = bands.index.year:select({ 1965 }, { iterator = 'GT', limit = 3 })
--[[
---
- - [9, 'Led Zeppelin', 1968]
- [10, 'Queen', 1970]
- [1, 'Roxette', 1986]
...
--]]
The :ref:`comparison operators <box_index-iterator-types>` are:
``LT`` for "less than"
``LE`` for "less than or equal"
``GT`` for "greater"
``GE`` for "greater than or equal"
``EQ`` for "equal"
``REQ`` for "reversed equal"
Value comparisons make sense if and only if the index type is TREE. The iterator types for other types of indexes are slightly different and work differently. See details in section :ref:`Iterator types <box_index-iterator-types>`.
Note that we don't use the name of the index, which means we use primary index here.
This type of search may return more than one tuple. The tuples will be sorted in descending order by key if the comparison operator is LT or LE or REQ. Otherwise they will be sorted in ascending order.
The search can use a **secondary index**.
-- Select a tuple by the specified secondary key value --
select_secondary = bands.index.band:select { 'The Doors' }
--[[
---
- - [7, 'The Doors', 1965]
...
--]]
**Partial key search:** The search may be for some key parts starting with the prefix of the key. Note that partial key searches are available only in TREE indexes.
-- Select tuples by the specified partial key value --
select_multipart_partial = bands.index.year_band:select { 1965 }
--[[
---
- - [5, 'Pink Floyd', 1965]
- [2, 'Scorpions', 1965]
- [7, 'The Doors', 1965]
...
--]]
The search can be for all fields, using a table as the value:

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testing_project / Documentation: how-to/db/indexes — English

-- Select maximum 3 tuples with the key value greater than 1965 --
select_greater = bands.index.year:select({ 1965 }, { iterator = 'GT', limit = 3 })
--[[
---
- - [9, 'Led Zeppelin', 1968]
- [10, 'Queen', 1970]
- [1, 'Roxette', 1986]
...
--]]
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