[OAK-10527] Improve readability of the explain query output

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.60.0
• Component/s: query
• Assignee: Thomas Mueller
• Reporter: Thomas Mueller
• Created: 02/Nov/23 13:51
• Updated: 06/Dec/23 18:49
• Resolved: 07/Nov/23 13:45

Description

Currently the output "explain query" of Oak (the query plan) is hard to interpret.
A more human-readable output would be better. Example:

Old:

[nt:base] as [nt:base] /* lucene:slingResourceResolver-1(/oak:index/slingResourceResolver-1) sling:vanityPath:[* TO *] sync:(sling:vanityPath is not null) where ([nt:base].[sling:vanityPath] is not null) and (first([nt:base].[sling:vanityPath]) > '') */

New:

[nt:base] as [nt:base] /* lucene:slingResourceResolver-1
    indexDefinition: /oak:index/slingResourceResolver-1
    estimatedEntries: 46
    luceneQuery: sling:vanityPath:[* TO *]
    synchronousPropertyCondition: sling:vanityPath is not null
 */

Also, the formatting of the logged query statement should be improved: instead of one single line with the whole statement, the statement should contain line breaks before the important keywords. Example:

Old:

Parsing JCR-SQL2 statement: explain SELECT [sling:vanityPath], [sling:redirect], [sling:redirectStatus] FROM [nt:base] WHERE NOT isdescendantnode('/jcr:system') AND [sling:vanityPath] IS NOT NULL AND FIRST([sling:vanityPath]) > '' ORDER BY FIRST([sling:vanityPath])

New:

Parsing JCR-SQL2 statement: explain SELECT [sling:vanityPath], [sling:redirect], [sling:redirectStatus]
  FROM [nt:base]
  WHERE NOT isdescendantnode('/jcr:system')
  AND [sling:vanityPath] IS NOT NULL
  AND FIRST([sling:vanityPath]) > ''
  ORDER BY FIRST([sling:vanityPath])

Issue Links

• links to: GitHub Pull Request #1187