{"uid":"cap_61NH__yG26mD2R2hK4jzY","slug":"sql-ddl-compatibility-checker-8d265518","name":"SQL DDL Compatibility Checker","description":"Compare two SQL schema snapshots and report what would break a client written against the first. Separates reader breakage from writer breakage, because the same change breaks different people: a dropped column breaks whoever selects it, a new NOT NULL column with no default breaks every existing insert. Also reports narrowed and widened types, lost defaults, nullability flips, collation changes and added or removed uniqueness.","url":"https://api.zfinia.com/x402/v1/sql-ddl-compatibility?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"role":{"enum":["readers","writers","both"],"type":"string"},"after":{"type":"string","maxLength":262144},"before":{"type":"string","maxLength":262144}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.28","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.28/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.28","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.28","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_0ZuWcyHpDlJes1XBzmzRa","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.28","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Compares two SQL schema snapshots and identifies breaking changes for readers, writers, or both, including dropped columns, type narrowing, nullability flips, and more.","exampleAgentPrompt":"Check if our schema migration will break anything — here's the old DDL and the new DDL, and I need to know about breakage for both readers and writers.","exampleUseCases":[{"title":"Pre-migration compatibility gate","prompt":"Before we run this migration in production, compare the before and after DDL and tell me everything that would break existing SELECT queries or INSERT statements — check for both readers and writers."},{"title":"CI pipeline schema diff check","prompt":"We just merged a PR that changes our users table schema. Here's the original DDL and the new one — flag any dropped columns, type narrowing, new NOT NULL columns without defaults, or nullability flips that would break our app."},{"title":"API contract backward compatibility","prompt":"Our data API exposes this SQL schema to external clients. I need to know if the proposed new schema would break any of those readers — just check the reader impact, not writers."}],"resultDescription":"A structured report listing breaking changes separated by reader impact and writer impact, including: dropped columns, type narrowing or widening, lost default values, nullability flips, collation changes, and added or removed uniqueness constraints. Each change is classified by which role (readers, writers, or both) it affects.","failureModes":["Invalid or unparseable SQL DDL in before/after fields returns a parse error","Exceeding the 262144 character limit per schema field returns a payload-too-large error","Missing required 'before' or 'after' fields returns a validation error","Payment failure or insufficient USDC balance returns a 402 error","Unsupported SQL dialect syntax may not be fully analyzed"],"whenToPreferThis":"Choose this endpoint when you need a semantic, role-aware breakdown of SQL schema breaking changes — specifically when you need to distinguish between what breaks readers vs writers. It goes beyond simple diffs by interpreting the migration impact on client behavior, making it ideal for CI/CD gates, migration review workflows, or API contract validation.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-11T18:38:51.445Z","isFirstParty":false,"canonicalSlug":"sql-ddl-compatibility-checker-8d265518"}