Skills.
Give your AI a better way to work.
A skill is a set of written instructions that teaches an AI how to do one job the way it should be done: review a pull request, plan a migration, write the release notes.
Install one here and it travels with your account into Claude, Claude Code, Cursor and every other client you sign in with.
Category: Databases & data
2,461 results · page 37 of 83
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sql-injection-stackedSkillDatabases & data
Guide stacked query SQL injection and second-order injection exploitation during authorized penetration testing.
Ready to connect★ 275
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sql-injection-unionSkillDatabases & data
Guide UNION-based SQL injection exploitation during authorized penetration testing.
Ready to connect★ 275
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setupSkillDatabases & data
Full development environment setup from scratch — prerequisites, dependencies, .env file, optional local PostgreSQL database (for auth/collections/chat work), and dev server. Use for first-time setup, broken environments, missing env vars, or when the app won't start.
Ready to connect★ 274
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clickhouse-aggregatingmergetree-state-mergeSkillDatabases & data
Fix ClickHouse query errors when querying AggregatingMergeTree tables that use state functions. Use when: (1) Query fails with type mismatch on AggregateFunction columns, (2) Using sum/count on columns created with sumState/countState/uniqState, (3) Creating views that JOIN with materialized views u
Ready to connect★ 264
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clickhouse-cloud-multi-table-renameSkillDatabases & data
Fix ClickHouse Cloud migration failures caused by multi-table RENAME statements. Use when: (1) Migration fails with "Database X is Shared, it does not support renaming of multiple tables in single query", (2) golang-migrate or other migration tools show dirty database version after a table-swap migr
Ready to connect★ 264
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clickhouse-materialized-column-view-filterSkillDatabases & data
Fix HTTP 500 / ClickHouse "column not found" errors when filtering by a MATERIALIZED column through a VIEW that doesn't expose it. Use when: (1) a WHERE clause references alias.column on a view but the column is MATERIALIZED on the underlying table, (2) the query works on the raw table but fails thr
Ready to connect★ 264
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clickhouse-nip33-addressable-dedupSkillDatabases & data
Fix duplicate Nostr events in ClickHouse when using ReplacingMergeTree for NIP-33 addressable events (Kind 30000+). Use when: (1) Edited videos/events appear as duplicates, (2) Same d_tag shows multiple events with different IDs, (3) FINAL keyword doesn't deduplicate properly for parameterized repla
Ready to connect★ 264
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clickhouse-rust-type-mismatchesSkillDatabases & data
Fix ClickHouse query errors in Rust when using clickhouse-rs crate. Use when: (1) "string is not valid utf8" errors - typically FixedString columns need CAST to String, (2) "tag for enum is not valid" errors - typically Option<T> fields receiving non-NULL values, (3) Sum/count aggregations returning
Ready to connect★ 264
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clickhouse-rust-view-column-orderSkillDatabases & data
Debug ClickHouse deserialization errors in Rust caused by column ORDER mismatch when using SELECT alias.* on a VIEW that adds computed columns. Use when: (1) Some query variants (e.g. sort=trending) return 500 but others (sort=recent) succeed, (2) Queries use SELECT view_alias.*, extra_cols FROM vie
Ready to connect★ 264
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clickhouse-system-log-disk-exhaustionSkillDatabases & data
Fix ClickHouse "Code: 243 Cannot reserve 1.00 MiB, not enough space" errors caused by system log tables (text_log, trace_log, processors_profile_log, query_log) filling the disk. Use when: (1) ClickHouse inserts fail with NOT_ENOUGH_SPACE error, (2) Disk is 100% full but application tables are small
Ready to connect★ 264
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cloud-run-job-cloudsql-setupSkillDatabases & data
Set up Cloud Run Jobs with CloudSQL connection. Use when: (1) Deploying long-running batch jobs that need database access, (2) Errors like "Cloud SQL Proxy not found" in container, (3) "password authentication failed" despite correct credentials, (4) Job creation fails with permission errors. Covers
Ready to connect★ 264
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cloudsql-idle-connection-timeoutSkillDatabases & data
Fix psycopg2 "could not receive data from server: Operation timed out" or "connection already closed" errors when using Cloud SQL with long-running Python scripts. Use when: (1) psycopg2.OperationalError after a period of no DB activity, (2) DB connection works initially but fails after a non-DB pha
Ready to connect★ 264
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funnelcake-deployment-workflowSkillDatabases & data
Deploy funnelcake (api + relay) to ANY environment (production, staging, poc) on GKE via ArgoCD. Use when: (1) Deploying new funnelcake commits, (2) Building Docker images for GKE (amd64), (3) Running ClickHouse migrations, (4) Troubleshooting ImagePullBackOff errors, (5) Syncing staging/poc after p
Ready to connect★ 264
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gorse-clickhouse-cloud-incompatibleSkillDatabases & data
Fix Gorse recommendation engine failing to connect to ClickHouse Cloud with EOF errors. Use when: (1) Gorse pods crash with "failed to connect data database" and "EOF" error, (2) Using ClickHouse Cloud (*.clickhouse.cloud) as Gorse data store, (3) TLS connection works (verified with openssl) but Gor
Ready to connect★ 264
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local-cache-idempotency-fallbackSkillDatabases & data
Use database cache when external APIs aren't reliably idempotent. Use when: (1) External API claims idempotency but returns different values for same input, (2) Re-running a script creates duplicate resources, (3) Need stable identifiers across runs but external service generates new ones. Pattern:
Ready to connect★ 264
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metadata-storage-source-of-truth-desyncSkillDatabases & data
Fix content serving failures caused by metadata (KV store, database) being out of sync with actual storage (GCS, S3, filesystem). Use when: (1) Content exists in storage but API returns "processing" or "not ready", (2) Webhook callbacks that update metadata failed silently, (3) Backfill scripts gene
Ready to connect★ 264
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multi-cluster-api-data-mismatchSkillDatabases & data
Debug "API returns data that doesn't exist in database" when multiple Kubernetes clusters exist (production, staging, POC). Use when: (1) REST API returns records that direct database queries can't find, (2) Data counts match approximately but specific records don't overlap, (3) kubectl context poin
Ready to connect★ 264
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postgres-concurrent-schema-init-deadlockSkillDatabases & data
Fix PostgreSQL deadlock errors caused by concurrent schema initialization in worker processes. Use when: (1) psycopg2.errors.DeadlockDetected during CREATE INDEX/TABLE IF NOT EXISTS, (2) Multiple Cloud Run jobs, Kubernetes pods, or worker processes start simultaneously, (3) Error shows "Process X wa
Ready to connect★ 264
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psycopg2-batch-insert-optimizationSkillDatabases & data
Optimize slow PostgreSQL inserts in Python using psycopg2. Use when: (1) Row-by-row inserts are taking too long over network, (2) executemany() isn't providing speedup, (3) Migrating large datasets to PostgreSQL, (4) Network latency making individual INSERT statements impractical. The key is using e
Ready to connect★ 264
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psycopg2-like-percent-escapeSkillDatabases & data
Fix psycopg2 "IndexError: tuple index out of range" when using LIKE with parameterized queries. Use when: (1) cursor.execute() fails with IndexError on a query containing LIKE '%pattern%', (2) SQL LIKE wildcards conflict with psycopg2 %s parameter placeholders, (3) Query works in psql but fails in P
Ready to connect★ 264
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rest-api-optimistic-update-race-conditionSkillDatabases & data
Fix "content disappears after publishing" bugs caused by REST API indexing lag. Use when: (1) User publishes content but it doesn't appear in their feed/profile, (2) REST API returns stale data immediately after write operations, (3) Async indexing backends (ClickHouse, Elasticsearch, etc.) haven't
Ready to connect★ 264
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sqlite-fts5-corruption-rebuildSkillDatabases & data
Fix SQLite "database disk image is malformed" errors caused by corrupted FTS5 indexes. Use when: (1) UPDATE/INSERT fails with "stepping, database disk image is malformed" but PRAGMA integrity_check returns "ok", (2) Only specific records fail to update while others succeed, (3) Records contain dirty
Ready to connect★ 264
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flyway-migrationsSkillDatabases & data
Use when creating database migrations, schema changes, seed data, or any SQL that modifies database structure. Covers Flyway naming conventions, versioning, and safe migration patterns.
Ready to connect★ 263
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idempotency-patternsSkillDatabases & data
Use when making retried HTTP commands or message processing safe against duplicate effects, including database-backed request keys, payload conflicts and concurrent retries. Do not apply caching as a substitute for business idempotency.
Ready to connect★ 263
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multi-tenancySkillDatabases & data
Use when implementing tenant resolution, database or schema isolation, tenant-aware JPA, reactive tenant context, migrations, caching, jobs, or authorization in Spring Boot 3.
Ready to connect★ 263
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spring-batchSkillDatabases & data
Use when building batch jobs, ETL pipelines, scheduled imports/exports, or any chunk-oriented bulk processing with Spring Batch. Covers the Spring Batch 5 / Boot 3 builder API, restartability and idempotent job parameters, reader/writer thread-safety, fault tolerance, and chunk transaction boundarie
Ready to connect★ 263
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spring-data-redisSkillDatabases & data
Use when implementing caching, session storage, rate limiting, or any Redis integration. Covers cache-aside pattern, key naming, TTL strategy, and serialization config.
Ready to connect★ 263
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transactional-patternsSkillDatabases & data
Use when working with @Transactional, multi-step database operations, distributed transactions, or any code that needs atomicity guarantees. Covers propagation rules, isolation levels, read-only optimization, and common pitfalls.
Ready to connect★ 263
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webSkillDatabases & data
Web security attack and defense techniques, including identification and exploitation of common vulnerabilities such as SQL injection, XSS, file upload, command injection, SSRF, and deserialization.
Ready to connect★ 263
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code-optimizerSkillDatabases & data
Analyzes and optimizes code for better performance, memory usage, and efficiency. Use when code is slow, memory-intensive, or inefficient. Supports Python and Java optimization including execution speed improvements, memory reduction, database query optimization, and I/O efficiency. Provides before/
Ready to connect★ 252
What is a skill?
A skill is plain text, usually a SKILL.md file and the scripts it refers to, written for an AI rather than for a person. It carries the steps, the house rules and the examples a good answer needs, so you stop pasting the same briefing into every new chat.
54,764 of the 55,196 skills listed here can be served through ahel today, and they come from public repositories. Each one has its own page with the instructions themselves on it, so you can read what a skill will tell your AI to do before you install it.
Install one and every AI you use gets it
Installing a skill adds it to your gateway and turns it on in the same step. Claude Code surfaces it as a slash command; any client can read the full instructions with the skill_read tool.
Nothing is copied into a project folder. The instructions are served from your account, so the same skill is there in every AI you connect, and turning it off removes it from all of them at once.