Use ORDERBY in calc_agg_tiles_hash - SQLite v3.44 (#1156)

Require SQLite v3.44+ ORDER BY clause inside aggregate function instead
of the windowing one - might solve out of memory issues reported by
users - see #1154
This commit is contained in:
Yuri Astrakhan 2024-01-27 21:48:54 -05:00 committed by GitHub
parent c4af48bba9
commit 74c67a3812
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 6 additions and 10 deletions

View File

@ -72,7 +72,7 @@ serde_with = "3"
serde_yaml = "0.9"
size_format = "1.0.2"
spreet = { version = "0.11", default-features = false }
sqlite-hashes = { version = "0.6", default-features = false, features = ["md5", "window", "hex"] }
sqlite-hashes = { version = "0.6", default-features = false, features = ["md5", "window", "hex"] } # window forces libsqlite3-sys to bundle sqlite3. We require v3.44.0 or newer.
sqlx = { version = "0.7", features = ["sqlite", "runtime-tokio"] }
subst = { version = "0.3", features = ["yaml"] }
thiserror = "1"

View File

@ -470,22 +470,18 @@ where
// `md5` functions will fail if the value is not text/blob/null
//
// Note that ORDER BY controls the output ordering, which is important for the hash value,
// and having it at the top level would not order values properly.
// and we must use ORDER BY as a parameter to the aggregate function itself (available since SQLite 3.44.0)
// See https://sqlite.org/forum/forumpost/228bb96e12a746ce
"
SELECT coalesce(
(SELECT md5_concat_hex(
md5_concat_hex(
cast(zoom_level AS text),
cast(tile_column AS text),
cast(tile_row AS text),
tile_data
)
OVER (ORDER BY zoom_level, tile_column, tile_row ROWS
BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING)
FROM tiles
LIMIT 1),
md5_hex('')
);
ORDER BY zoom_level, tile_column, tile_row),
md5_hex(''))
FROM tiles;
",
);
Ok(query.fetch_one(conn).await?.get::<String, _>(0))