42590ae64b
* Refresh query docs. Larger changes: - New doc: querying/datasource.md describes the various kinds of datasources you can use, and has examples for both SQL and native. - New doc: querying/query-execution.md describes how native queries are executed at a high level. It doesn't go into the details of specific query engines or how queries run at a per-segment level. But I think it would be good to add or link that content here in the future. - Refreshed doc: querying/sql.md updated to refer to joins, reformatted a bit, added a new "Query translation" section that explains how queries are translated from SQL to native, and removed configuration details (moved to configuration/index.md). - Refreshed doc: querying/joins.md updated to refer to join datasources. Smaller changes: - Add helpful banners to the top of query documentation pages telling people whether a given page describes SQL, native, or both. - Add SQL metrics to operations/metrics.md. - Add some color and cross-links in various places. - Add native query component docs to the sidebar, and renamed them so they look nicer. - Remove Select query from the sidebar. - Fix Broker SQL configs in configuration/index.md. Remove them from querying/sql.md. - Combined querying/searchquery.md and querying/searchqueryspec.md. * Updates. * Fix numbering. * Fix glitches. * Add new words to spellcheck file. * Assorted changes. * Further adjustments. * Add missing punctuation.
2.8 KiB
| id | title |
|---|---|
| sorting-orders | String comparators |
Apache Druid supports two query languages: Druid SQL and native queries. This document describes the native language. For information about functions available in SQL, refer to the SQL documentation.
These sorting orders are used by the TopNMetricSpec, SearchQuery, GroupByQuery's LimitSpec, and BoundFilter.
Lexicographic
Sorts values by converting Strings to their UTF-8 byte array representations and comparing lexicographically, byte-by-byte.
Alphanumeric
Suitable for strings with both numeric and non-numeric content, e.g.: "file12 sorts after file2"
See https://github.com/amjjd/java-alphanum for more details on how this ordering sorts values.
This ordering is not suitable for numbers with decimal points or negative numbers.
- For example, "1.3" precedes "1.15" in this ordering because "15" has more significant digits than "3".
- Negative numbers are sorted after positive numbers (because numeric characters precede the "-" in the negative numbers).
Numeric
Sorts values as numbers, supports integers and floating point values. Negative values are supported.
This sorting order will try to parse all string values as numbers. Unparseable values are treated as nulls, and nulls precede numbers.
When comparing two unparseable values (e.g., "hello" and "world"), this ordering will sort by comparing the unparsed strings lexicographically.
Strlen
Sorts values by the their string lengths. When there is a tie, this comparator falls back to using the String compareTo method.
Version
Sorts values as versions, e.g.: "10.0 sorts after 9.0", "1.0.0-SNAPSHOT sorts after 1.0.0".
See https://maven.apache.org/ref/3.6.0/maven-artifact/apidocs/org/apache/maven/artifact/versioning/ComparableVersion.html for more details on how this ordering sorts values.