Mention limitations

akrylysov · Jan 1, 2024 · 794a326 · 794a326
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diff --git a/README.md b/README.md
@@ -111,3 +111,7 @@ on DigitalOcean 8 CPUs / 16 GB RAM / 160 GB SSD + Ubuntu 16.04.3 (higher is bett
 ## Internals
 
 [Design document](/docs/design.md).
+
+## Limitations
+
+The design choices made to optimize for point lookups bring limitations for other potential use-cases. For example, using a hash table for indexing makes range scans impossible. Additionally, having a single hash table shared across all WAL segments makes the recovery process require rebuilding the entire index, which may be impractical for large databases.
diff --git a/docs/design.md b/docs/design.md
@@ -186,3 +186,7 @@ After the compaction is successfully finished, the compacted segment files are r
 In the event of a crash caused by a power loss or an operating system failure, Pogreb discards the index and replays the
 WAL building a new index from scratch.
 Segments are iterated from the oldest to the newest and items are inserted into the index.
+
+# Limitations
+
+The design choices made to optimize for point lookups bring limitations for other potential use-cases. For example, using a hash table for indexing makes range scans impossible. Additionally, having a single hash table shared across all WAL segments makes the recovery process require rebuilding the entire index, which may be impractical for large databases.