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add tombstoneUserSnapshots to ClickHouseStore
Bulk-tombstones all non-deleted post snapshots for an author via a
single INSERT ... SELECT FROM ... FINAL, using positional column
mapping to avoid ClickHouse's alias-shadowing issue in WHERE clauses.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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packages/clickhouse/src/store.ts
+48
packages/clickhouse/src/store.ts
···
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)
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}
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}
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/**
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* Bulk-tombstones all currently non-deleted post snapshots for an author.
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*
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* Uses a single INSERT ... SELECT to copy every non-deleted row for the
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* author with is_deleted=1 and a fresh snapshot_taken_at. The
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* ReplacingMergeTree engine will, on the next merge, pick the row with
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* the largest snapshot_taken_at per (post_author_did, post_uri), and the
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* is_deleted=1 rows win because they have a newer snapshot_taken_at.
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*
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* Called when an account deletion or takedown event arrives for a tracked user.
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*/
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async tombstoneUserSnapshots(authorDid: string): Promise<void> {
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// NOTE: Column aliases (e.g. "now64(6) AS snapshot_taken_at") are intentionally
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// omitted from this INSERT SELECT because ClickHouse evaluates SELECT aliases
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// before the WHERE clause — so "1 AS is_deleted" in the SELECT would shadow the
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// column reference in "WHERE is_deleted = 0", causing the filter to evaluate as
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// "1 = 0" (always false) and return zero rows. Using positional column mapping
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// (column order instead of aliases) avoids this aliasing trap.
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const sql = `
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INSERT INTO post_snapshots
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SELECT
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post_uri,
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post_author_did,
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post_text,
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post_created_at,
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snapshot_likes,
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snapshot_reposts,
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snapshot_quotes,
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now64(6),
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toUInt8(1)
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FROM post_snapshots FINAL
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WHERE post_author_did = {authorDid:String}
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AND is_deleted = 0
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`
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try {
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await this.client.command({
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query: sql,
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query_params: { authorDid },
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})
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} catch (err) {
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throw new Error(
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`ClickHouseStore.tombstoneUserSnapshots failed for author ${authorDid}`,
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{ cause: err },
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)
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}
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}
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}