Event reads filtered on source and every modified-value read filtered on tag
scanned that symbol column in every partition of the window; only
sample.tag carried an index (#683).
Both columns are now SYMBOL INDEX in the DDL, and the bootstrapper's index
migration is generalised over QuestDbTables.SymbolIndexes (sample.tag,
event.source, sample_modified.tag): a missing index is added with the same
idempotent ALTER ... ADD INDEX, Warning-only when AutoCreateSchema is false
or the ALTER is refused. Integration tests: new tables carry all three; a
pre-index table set gains them on boot and event reads answer the same.
This reverses #683's documented choice to leave the two unindexed;
docs/Historian.md carries the reasoning.
Rebased from the unpushed remed/lane-H2 branch (originally authored 2026-10-22
in session_01Ub9hGmYLQvn9XETzw7CMsT) onto current master.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
Joseph Doherty
bc2f5e1889