fix: merge strategy is memory intensive#9054
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begelundmuller
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begelundmuller
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runtime/drivers/duckdb/crud.go
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| // Create a temporary table with the new data | ||
| tmp := uuid.New().String() | ||
| _, err := conn.ExecContext(ctx, fmt.Sprintf("CREATE TEMPORARY TABLE %s AS (%s\n)", safeSQLName(tmp), sql)) | ||
| _, err := conn.ExecContext(ctx, fmt.Sprintf("CREATE TABLE %s AS (%s\n)", safeSQLName(tmp), sql)) |
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Can you see a way this can be done with a stable random name rather than a new UUID every time?
There are various error cases where we can't rely on automatic clean up (e.g. OOM or SIGKILL). Generally when using non-temporary resources, we try to use stable names and CREATE OR REPLACE to keep things idempotent and ensure eventual cleanup in later retries (or at least bounded growth of temporary data).
runtime/drivers/duckdb/crud.go
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| tmp := uuid.New().String() | ||
| _, err := conn.ExecContext(ctx, fmt.Sprintf("CREATE TEMPORARY TABLE %s AS (%s\n)", safeSQLName(tmp), sql)) | ||
| _, err := conn.ExecContext(ctx, fmt.Sprintf("CREATE TABLE %s AS (%s\n)", safeSQLName(tmp), sql)) |
begelundmuller
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k-anshul
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* fix: merge strategy is compute intensive * tables need drop now * use gracful ctx * review comments
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closes https://linear.app/rilldata/issue/PLAT-437/improve-oomes-in-duckdb-when-ingesting-partitions-with-merge-strategy
deleteandinsertstatements executed in merge are probably not intensive. I tried by copying a big table and doing delete followed by insert. Both executed pretty fast, did not generate any tmp files ifpreserve_insertion_orderis false.Checklist: