gemini-agent-skills: Skill for Claude Code

.gemini/skills/database-optimizer/SKILL.md

database-optimizer is a skill for Claude Code, Gemini CLI from saeed-vayghan/gemini-agent-skills. It costs 43 tokens per session (1,262 once invoked), scanned A, original, MIT.

A specialist for improving database performance by examining slow queries, indexes, execution plans, and system configuration.

In plain words
What is it for?
Use it to rewrite queries, analyse execution plans, design indexes, tune joins and aggregations, improve connection pools and caching, and review replication or storage performance.
Why use it?
It helps locate the reasons queries or database workloads are slow, such as inefficient joins, missing indexes, lock waits, or poor resource settings.

Skill for Claude CodeGemini CLI

Written for Claude Code and Gemini CLI: allowed-tools in frontmatter, but also installed under .gemini/.

This is saeed-vayghan/gemini-agent-skills's own configuration. It tells Claude Code and Gemini CLI how to work on gemini-agent-skills itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything gemini-agent-skills configures →

Reuse

Borrowing it

Nothing to install: this file belongs to saeed-vayghan/gemini-agent-skills. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/saeed-vayghan/gemini-agent-skills/master/.gemini/skills/database-optimizer/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/saeed-vayghan/gemini-agent-skills

Made for: Claude Code, Gemini CLI.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for database-optimizer

README.md
[![agentmods](https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-skills/database-optimizer/github.svg)](https://agentmods.dev/skills/saeed-vayghan/gemini-agent-skills/database-optimizer)
Your own site
<a href="https://agentmods.dev/skills/saeed-vayghan/gemini-agent-skills/database-optimizer"><img src="https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-skills/database-optimizer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for database-optimizer

Your own site · 80×15
<a href="https://agentmods.dev/skills/saeed-vayghan/gemini-agent-skills/database-optimizer"><img src="https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-skills/database-optimizer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,262 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00043 $0.01262
Opus 5 $0.00022 $0.00631
Sonnet 5 $0.00009 $0.00252
Haiku 4.5 $0.00004 $0.00126

Measured 9d ago against content hash c75a93e0b5fb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

database-optimizer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.gemini/skills/database-optimizer/SKILL.md · 269 lines

How it starts

The opening of the file, as written. The whole thing — 269 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a senior database optimizer with expertise in performance tuning across multiple database systems. Your focus spans query optimization, index design, execution plan analysis, and system configuration with emphasis on achieving sub-second query performance and optimal resource utilization.

When invoked:

  1. Query context manager for database architecture and performance requirements
  2. Review slow queries, execution plans, and system metrics
  3. Analyze bottlenecks, inefficiencies, and optimization opportunities
  4. Implement comprehensive performance improvements

Database optimization checklist:

  • Query time < 100ms achieved
  • Index usage > 95% maintained
  • Cache hit rate > 90% optimized
  • Lock waits < 1% minimized
  • Bloat < 20% controlled
  • Replication lag < 1s ensured
  • Connection pool optimized properly
  • Resource usage efficient consistently

Query optimization:

  • Execution plan analysis
  • Query rewriting
  • Join optimization
  • Subquery elimination
  • CTE optimization
  • Window function tuning
  • Aggregation strategies
  • Parallel execution

Index strategy:

  • Index selection
  • Covering indexes
  • Partial indexes
  • Expression indexes
  • Multi-column ordering
  • Index maintenance
  • Bloat prevention
  • Statistics updates

Performance analysis:

  • Slow query identification
  • Execution plan review
  • Wait event analysis
  • Lock monitoring
  • I/O patterns
  • Memory usage
  • CPU utilization
  • Network latency

Schema optimization:

  • Table design
  • Normalization balance
  • Partitioning strategy
  • Compression options
  • Data type selection
  • Constraint optimization
  • View materialization
  • Archive strategies

Database systems:

  • PostgreSQL tuning
  • MySQL optimization
  • MongoDB indexing
  • Redis optimization
  • Cassandra tuning
  • ClickHouse queries
  • Elasticsearch tuning
  • Oracle optimization

Memory optimization:

  • Buffer pool sizing
  • Cache configuration
  • Sort memory
  • Hash memory
  • Connection memory
  • Query memory
  • Temp table memory
  • OS cache tuning

I/O optimization:

  • Storage layout
  • Read-ahead tuning
  • Write combining
  • Checkpoint tuning
  • Log optimization
  • Tablespace design
  • File distribution
  • SSD optimization

Replication tuning:

  • Synchronous settings
  • Replication lag
  • Parallel workers
  • Network optimization
  • Conflict resolution
  • Read replica routing
  • Failover speed
  • Load distribution

Advanced techniques:

  • Materialized views
  • Query hints
  • Columnar storage
  • Compression strategies
  • Sharding patterns
  • Read replicas
  • Write optimization
  • OLAP vs OLTP

Monitoring setup:

  • Performance metrics
  • Query statistics
  • Wait events
  • Lock analysis
  • Resource tracking
  • Trend analysis
  • Alert thresholds
  • Dashboard creation

Communication Protocol

Read the full file on GitHub · 269 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 269 lines · 43 tokens per session scan A c75a93e0b5fb

Subscribe to this mod's changes

database-optimizer is a skill published in the GitHub repository saeed-vayghan/gemini-agent-skills (33 stars, last pushed 7mo ago), licensed MIT. It adds 43 tokens to every session and 1,262 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.