SAI Quickstart
To get started with Storage-Attached Indexing (SAI), we’ll do the following steps:
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Create a keyspace.
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Create a table.
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Create an index using SAI.
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Add data.
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Create and run a query using SAI.
The examples in this quickstart topic show SAI indexes with non-partition key columns.
Create a keyspace
In cqlsh
, define the cycling
keyspace to try the commands in a test environment:
CREATE KEYSPACE IF NOT EXISTS cycling
WITH REPLICATION = {
'class' : 'SimpleStrategy',
'replication_factor' : 1
};
Create a database table
Using cqlsh
or the CQL Console, create a cyclist_semi_pro
database table in the cycling
keyspace or the keyspace name of your choice:
CREATE TABLE IF NOT EXISTS cycling.cyclist_semi_pro (
id int,
firstname text,
lastname text,
age int,
affiliation text,
country text,
registration date,
PRIMARY KEY (id));
Create SAI indexes on the database table
To test a non-trivial query, you’ll need some SAI indexes.
Use CREATE CUSTOM INDEX commands to create SAI indexes on a few non-primary-key columns in the cyclist_semi_pro
table:
CREATE CUSTOM INDEX lastname_idx ON cycling.cyclist_semi_pro (lastname)
USING 'StorageAttachedIndex'
WITH OPTIONS = {'case_sensitive': 'false', 'normalize': 'true', 'ascii': 'true'};
CREATE CUSTOM INDEX age_idx ON cycling.cyclist_semi_pro (age)
USING 'StorageAttachedIndex';
CREATE CUSTOM INDEX country_idx ON cycling.cyclist_semi_pro (country)
USING 'StorageAttachedIndex'
WITH OPTIONS = {'case_sensitive': 'false', 'normalize': 'true', 'ascii': 'true'};
CREATE CUSTOM INDEX registration_idx ON cycling.cyclist_semi_pro (registration)
USING 'StorageAttachedIndex';
Index names are unique per keyspace. The index name must be a unique identifier for the index for each table within a keyspace. Enclose in quotes to use special characters or preserve capitalization. If you do not specify an index name, CQL generates one for you, with the pattern <table_name>_<column_name>_idx. This requirement is true for all indexes.
Let’s take a look at the description of the table and its indexes:
-
Query
-
Result
DESCRIBE TABLE cycling.cyclist_semi_pro;
CREATE TABLE cycling.cyclist_semi_pro (
id int PRIMARY KEY,
affiliation text,
age int,
country text,
firstname text,
lastname text,
registration date
) WITH bloom_filter_fp_chance = 0.01
AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'}
AND comment = ''
AND compaction = {'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'max_threshold': '32', 'min_threshold': '4'}
AND compression = {'chunk_length_in_kb': '64', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'}
AND crc_check_chance = 1.0
AND dclocal_read_repair_chance = 0.1
AND default_time_to_live = 0
AND gc_grace_seconds = 864000
AND max_index_interval = 2048
AND memtable_flush_period_in_ms = 0
AND min_index_interval = 128
AND read_repair_chance = 0.0
AND speculative_retry = '99PERCENTILE';
Add data to your table
Use CQLSH INSERT
commands to add some data to the cyclist_semi_pro
database table:
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (1, 'Carlos', 'Perotti', 22, 'Recco Club', 'ITA', '2020-01-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (2, 'Giovani', 'Pasi', 19, 'Venezia Velocità', 'ITA', '2016-05-15');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (3, 'Frances', 'Giardello', 24, 'Menaggio Campioni', 'ITA', '2018-07-29');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (4, 'Mark', 'Pastore', 19, 'Portofino Ciclisti', 'ITA', '2017-06-16');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (5, 'Irene', 'Cantona', 24, 'Como Velocità', 'ITA', '2012-07-22');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (6, 'Hugo', 'Herrera', 23, 'Bellagio Ciclisti', 'ITA', '2004-02-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (7, 'Marcel', 'Silva', 21, 'Paris Cyclistes', 'FRA', '2018-04-28');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (8, 'Theo', 'Bernat', 19, 'Nice Cavaliers', 'FRA', '2007-05-15');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (9, 'Richie', 'Draxler', 24, 'Normandy Club', 'FRA', '2011-02-26');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (10, 'Agnes', 'Cavani', 22, 'Chamonix Hauteurs', 'FRA', '2020-01-02');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (11, 'Pablo', 'Verratti', 19, 'Chamonix Hauteurs', 'FRA', '2006-05-15');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (12, 'Charles', 'Eppinger', 24, 'Chamonix Hauteurs', 'FRA', '2018-07-29');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (13, 'Stanley', 'Trout', 30, 'Bolder Boulder', 'USA', '2016-02-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (14, 'Juan', 'Perez', 31, 'Rutgers Alumni Riders', 'USA', '2017-06-16');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (15, 'Thomas', 'Fulton', 27, 'Exeter Academy', 'USA', '2012-12-15');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (16, 'Jenny', 'Hamler', 28, 'CU Alums Crankworkz', 'USA', '2012-07-22');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (17, 'Alice', 'McCaffrey', 26, 'Pennan Power', 'GBR', '2020-02-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (18, 'Nicholas', 'Burrow', 26, 'Aberdeen Association', 'GBR', '2016-02-12');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (19, 'Tyler', 'Higgins', 24, 'Highclere Agents', 'GBR', '2019-07-31');
INSERT INTO cycling.cyclist_semi_pro (id, firstname, lastname, age, affiliation, country, registration) VALUES (20, 'Leslie', 'Boyd', 18, 'London Cyclists', 'GBR', '2012-12-15');
Adding data in this quickstart topic shows simple INSERT
commands.
To load databases with many rows, consider using DataStax Bulk Loader for Apache Cassandra.
Try out CQL queries
Use the CQLSH SELECT
command to submit queries.
The supported query operators for tables with SAI indexes:
The unsupported query operators for tables with SAI indexes:
|
Find a specific semi-pro cyclist:
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Query
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Result
SELECT * FROM cycling.cyclist_semi_pro
WHERE lastname : 'Eppinger';
Find semi-pro cyclists whose age is less than or equal to 23:
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Query
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Result
SELECT * FROM cycling.cyclist_semi_pro WHERE age <= 23;
Find semi-pro cyclists from Great Britain:
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Query
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Result
SELECT * FROM cycling.cyclist_semi_pro
WHERE country : 'GBR';
Find semi-pro cyclists who registered between a given date range:
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Query
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Result
SELECT * FROM cycling.cyclist_semi_pro
WHERE registration > '2010-01-01' AND registration < '2015-12-31' LIMIT 10;
For query examples with |
Removing an SAI index
To remove an SAI index, use DROP INDEX
.
Example:
DROP INDEX IF EXISTS cycling.age_sai_idx;
See also:
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Using SAI examines column index and query rules, plus collection maps.