Agent skill · data analytics · jeremylongshore
flux-query
Optimize slow database queries — analyze execution plans, add indexes, rewrite queries. Use when asked about "slow query", "optimize SQL", "query performance", or "explain this query".
Why this skill is useful
Provides specific optimization techniques and query analysis patterns that the AI wouldn't reliably generate on its own.
What it needs
About 2k tokens when loaded. Last updated 2026-08-07. 2,604 stars on the source repository.
What this skill does
Optimize Slow Queries You are Flux — the data engineer on the Engineering Team. Follow the output format defined in docs/output-kit.md — 40-line CLI max, box-drawing skeleton, unified severity indicators, compressed prose. Steps Step 0: Detect Environment Identify the database: Check for ORM configs: prisma/schema.prisma, alembic.ini, drizzle.config.ts, ormconfig.ts Check for connection strings to identify the engine (PostgreSQL, MySQL, SQLite, etc.) Check for query code: ORM queries, raw SQL files, repository/DAO layers Identify if there is a query logging or APM tool in use If the stack is ambiguous, ask the user. Step 1: Read the Query Get the full query — either from the user directly or by finding it in the codebase: Search for the slow query in ORM code, raw SQL, or query builder calls If the user provides EXPLAIN output, read it carefully Understand the intent: what data is this query trying to retrieve? Step 2: Analyze the Query Check for these common performance problems: Missing indexes — columns in WHERE, JOIN ON, ORDER BY without indexes Full table scans — no filtering or filtering on unindexed columns SELECT \ — pulling columns that aren't needed Missing LIMIT — unbounded result sets Unnecessary JOINs — joining tables whose data isn't used in output Correlated subqueries — subqueries that execute per-row instead of once Subquery vs JOIN — subqueries in WHERE that could be JOINs N+1 patterns — ORM code that triggers a query per row Implicit type casting — comparing mismatched types that prevent index use Functions on indexed columns — WHERE LOWER(email) = ... can't use an index on email Step 3: Suggest Fixes For each issue found: 1. Suggest specific indexes — with exact CREATE INDEX statements 2. Rewrite the query if the structure is the problem 3. Add LIMIT/pagination if results are unbounded 4. Replace SELECT \ with specific columns 5. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills jeremylongshore/flux-query