From 015e1f9738b2b0d0e85765a9fbb22dab34d7ea36 Mon Sep 17 00:00:00 2001 From: "google-labs-jules[bot]" <161369871+google-labs-jules[bot]@users.noreply.github.com> Date: Thu, 11 Jun 2026 17:57:30 +0000 Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Optimize=20SQL=20statement?= =?UTF-8?q?=20generation=20in=20D1ExportContext?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Co-authored-by: bashandbone <89049923+bashandbone@users.noreply.github.com> --- .jules/bolt.md | 4 ++ crates/flow/src/targets/d1.rs | 75 +++++++++++++++++++++-------------- 2 files changed, 49 insertions(+), 30 deletions(-) diff --git a/.jules/bolt.md b/.jules/bolt.md index fb3e8f1..4f588c4 100644 --- a/.jules/bolt.md +++ b/.jules/bolt.md @@ -2,3 +2,7 @@ ## 2026-04-08 - [Performance: Defer Allocation during Traversal] **Learning:** During DAG traversals, creating owned variants of identifiers (like `file.to_path_buf()`) *before* checking `visited` HashSets results in heap allocations (O(E)) for every edge instead of every visited node (O(V)). By moving the `&PathBuf` allocation strictly *after* all HashSet `contains` checks using the borrowed reference (`&Path`), we drastically reduce memory churn. **Action:** Always check `HashSet::contains` with a borrowed reference *before* creating the owned version required by `HashSet::insert`, especially in performance-critical graph traversal paths. + +## 2024-05-18 - [Performance: Optimizing SQL string generation] +**Learning:** Generating SQL statements dynamically in `D1ExportContext` by using intermediate string allocations and vectors (e.g. `vec![]` then `join(", ")`) incurs significant overhead. Direct formatted writes to a pre-allocated `String` using `std::fmt::Write` reduces allocations and drastically improves statement generation performance. +**Action:** Replace intermediate vectors and string slices with single, pre-allocated strings (`String::with_capacity()`) and `write!()` macros in performance critical SQL statement construction logic. diff --git a/crates/flow/src/targets/d1.rs b/crates/flow/src/targets/d1.rs index e45fd52..aec6e69 100644 --- a/crates/flow/src/targets/d1.rs +++ b/crates/flow/src/targets/d1.rs @@ -300,40 +300,52 @@ impl D1ExportContext { key: &KeyValue, values: &FieldValues, ) -> Result<(String, Vec), RecocoError> { - let mut columns = vec![]; - let mut placeholders = vec![]; - let mut params = vec![]; - let mut update_clauses = vec![]; + use std::fmt::Write; + + // ⚡ Bolt: Pre-allocate capacity and avoid intermediate vectors + let num_keys = key.0.len().min(self.key_fields_schema.len()); + let num_values = values.fields.len().min(self.value_fields_schema.len()); + let total_cols = num_keys + num_values; + + let mut params = Vec::with_capacity(total_cols); + let mut sql = String::with_capacity(64 + total_cols * 15 + num_values * 30); + + write!(sql, "INSERT INTO {} (", self.table_name).unwrap(); - // Extract key parts - KeyValue is a wrapper around Box<[KeyPart]> + let mut first = true; for (idx, _key_field) in self.key_fields_schema.iter().enumerate() { if let Some(key_part) = key.0.get(idx) { - columns.push(self.key_fields_schema[idx].name.clone()); - placeholders.push("?".to_string()); + if !first { sql.push_str(", "); } + sql.push_str(&self.key_fields_schema[idx].name); params.push(key_part_to_json(key_part)?); + first = false; } } - // Add value fields for (idx, value) in values.fields.iter().enumerate() { if let Some(value_field) = self.value_fields_schema.get(idx) { - columns.push(value_field.name.clone()); - placeholders.push("?".to_string()); + if !first { sql.push_str(", "); } + sql.push_str(&value_field.name); params.push(value_to_json(value)?); - update_clauses.push(format!( - "{} = excluded.{}", - value_field.name, value_field.name - )); + first = false; } } - let sql = format!( - "INSERT INTO {} ({}) VALUES ({}) ON CONFLICT DO UPDATE SET {}", - self.table_name, - columns.join(", "), - placeholders.join(", "), - update_clauses.join(", ") - ); + sql.push_str(") VALUES ("); + for i in 0..params.len() { + if i > 0 { sql.push_str(", "); } + sql.push('?'); + } + + sql.push_str(") ON CONFLICT DO UPDATE SET "); + let mut first_update = true; + for (idx, _value) in values.fields.iter().enumerate() { + if let Some(value_field) = self.value_fields_schema.get(idx) { + if !first_update { sql.push_str(", "); } + write!(sql, "{0} = excluded.{0}", value_field.name).unwrap(); + first_update = false; + } + } Ok((sql, params)) } @@ -342,22 +354,25 @@ impl D1ExportContext { &self, key: &KeyValue, ) -> Result<(String, Vec), RecocoError> { - let mut where_clauses = vec![]; - let mut params = vec![]; + use std::fmt::Write; + + // ⚡ Bolt: Pre-allocate capacity and avoid intermediate vectors + let num_keys = key.0.len().min(self.key_fields_schema.len()); + let mut params = Vec::with_capacity(num_keys); + let mut sql = String::with_capacity(32 + num_keys * 20); + write!(sql, "DELETE FROM {} WHERE ", self.table_name).unwrap(); + + let mut first = true; for (idx, _key_field) in self.key_fields_schema.iter().enumerate() { if let Some(key_part) = key.0.get(idx) { - where_clauses.push(format!("{} = ?", self.key_fields_schema[idx].name)); + if !first { sql.push_str(" AND "); } + write!(sql, "{} = ?", self.key_fields_schema[idx].name).unwrap(); params.push(key_part_to_json(key_part)?); + first = false; } } - let sql = format!( - "DELETE FROM {} WHERE {}", - self.table_name, - where_clauses.join(" AND ") - ); - Ok((sql, params)) }