IndexTable

The index type table is used to look up metrics that match the query.

CREATE TABLE graphite_index (
  Date Date,
  Level UInt32,
  Path String,
  Version UInt32
) ENGINE = ReplacingMergeTree(Version)
PARTITION BY toYYYYMM(Date)
ORDER BY (Level, Path, Date);

Where:

• Date - date from received point. Or constant date for full metric list (1970-02-12 by default)
• Level - metric name nesting level
• Version - time when the last point was received

Each metric spawns multiple entries in a table:

• daily
• daily with reversed Path and Level = 10000+OriginalLevel
• records with constant Date and Level = 20000+OriginalLevel for metric itself and all it parents
• record with constant Date, reversed Path and Level = 30000+OriginalLevel

For example, getting the metric lorem.ipsum.dolor.sit.amet adds the following entries to the table:

Date	Level	Path	Version
2019-05-14	5	lorem.ipsum.dolor.sit.amet	1557827619
2019-05-14	10005	amet.sit.dolor.ipsum.lorem	1557827619
1970-02-12	20001	lorem.	1557827619
1970-02-12	20002	lorem.ipsum.	1557827619
1970-02-12	20003	lorem.ipsum.dolor.	1557827619
1970-02-12	20004	lorem.ipsum.dolor.sit.	1557827619
1970-02-12	20005	lorem.ipsum.dolor.sit.amet	1557827619
1970-02-12	30005	amet.sit.dolor.ipsum.lorem	1557827619

Migrate from tree table

-- direct Path and parents
INSERT INTO graphite_index (Date, Level, Path, Version) 
SELECT 
  '1970-02-12',
  Level,
  Path,
  Version 
FROM graphite_tree;

-- reversed Path
INSERT INTO graphite_index (Date, Level, Path, Version) 
SELECT 
  '1970-02-12',
  Level,
  arrayStringConcat(arrayMap(x->reverse(x), splitByChar('.', reverse(Path))), '.'),
  Version 
FROM graphite_tree
WHERE NOT Path LIKE '%.';

If you have not used series table and want to keep this behavior you should set index-use-daily = false in graphite-clickhouse config.