Hacktoberfest 2026:維護者為十月標記出來的 issue,仍然開放、適合新手。 瀏覽 Hacktoberfest issue

perf(catalog): ERD neighbourhood and MCP describe/sample read the whole schema catalog; filter tables in SQL

未關閉
#1,572 0 則留言 0 個 reaction 已指派 0 人 在 GitHub 檢視

維護者通常 1 天內回覆

還沒有人認領這個 Issue。

評估

難度
4/5
預估耗時
3-5 天
新手友好度
42/100
Issue 類型
缺陷
描述清晰度
描述清楚
活躍度
活躍
技術堆疊
dart, mysql, postgresql, sqlite

研究方向

Start with lib/core/erd/erd_catalog.dart:198-248 and lib/core/mcp/mcp_query_service.dart:245-270, then inspect the columnsSql and viewColumnsSql definitions for PostgreSQL, MySQL, and SQLite. Trace how ERD neighbourhood names and MCP table validation flow into those queries, and review the related tests. Done means SQL filters catalog reads to the requested tables, MCP uses a cheap existence check where appropriate, and a neighbourhood remains complete beyond the catalog row limit.

由索引模型根據 Issue 內容生成。

描述

backend core P3 performance

Problem

Two paths read the whole schema catalog when they need a few tables:

  1. ERD neighbourhood (ErdCatalog.loadNeighbourhood, lib/core/erd/erd_catalog.dart:198-248). It loads all FKs (needed for the graph walk), then for every schema in the neighbourhood runs columnsSql for all columns of that schema and filters in Dart (if (names.contains(r[0])), :230/:238). The PostgreSQL columnsSql has per-column correlated subqueries (unique-index EXISTS, pg_enum string_agg, col_description, pg_get_expr), so the cost grows with the schema, not with the diagram. With catalogRowLimit = 200000 (:19) a large schema is truncated before filtering, so the focused table can lose its columns even though it needs only a few rows.
  2. MCP describe_table / sample_rows (McpQueryService._loadCatalog, lib/core/mcp/mcp_query_service.dart:245-270). To find one table it runs three catalog queries over the whole schema (columns, FKs, view columns) on every call. sample_rows uses the result only to validate the table name.

Fix

  • Add a table filter to columnsSql / viewColumnsSql: PostgreSQL c.relname = ANY($names) per schema, MySQL table_name IN (...), SQLite m.name IN (...) (literal-escaped as in _lit, or bind parameters where the delegate supports them).
  • ERD neighbourhood: walk FKs first, then fetch columns only for the resulting names.
  • MCP: validate the name with a cheap existence query (to_regclass / information_schema.tables / sqlite_master), and describe one table with the filtered column/FK queries. Keep the full catalog only for list_tables and the schema:// resource.
  • Tests: the generated SQL contains the filter; the neighbourhood of a table in a schema larger than the row limit is complete.

Related: ERD epic #1166 and #1167 (same catalog SQL).

主要語言
Dart
星號
23
分支
1
平均合併
31 分鐘
30 天內合併 PR
570

環境準備

在 Codespaces 中開啟

在瀏覽器裡用你自己的 GitHub 帳號啟動這個專案的開發容器。

從這裡開始

  1. 先讀完整個 Issue,再讀專案的貢獻指南。
  2. 在 Issue 下留言說明你要接手 —— 這能避免兩個人做同樣的事。
  3. Fork 儲存庫,在一個分支上完成修改。
  4. 送出 Pull Request,並在描述裡引用這個 Issue 編號。

QueryaHub/Querya-Desktop 的其他 Issue

查看 QueryaHub/Querya-Desktop 的全部 Issue

相似的 Issue

更多 Dart Issue

把新 issue 寄到你的電子郵件信箱

精選適合新手參與的 GitHub issue 摘要。