Semantic D1 MCP

/** * 🎯 SEMANTIC INTENT: ForeignKey represents referential integrity relationship * * WHY: Foreign keys are semantic relationship markers * - Preserve referential integrity between tables * - Define cascade/restrict behavior semantics * - Observable from PRAGMA foreign_key_list * * OBSERVABLE PROPERTIES: Directly observable from database schema * SEMANTIC ANCHORING: Foreign keys indicate intentional data relationships * IMMUTABILITY: Frozen to preserve relationship semantics */ export type OnDeleteAction = 'CASCADE' | 'SET NULL' | 'SET DEFAULT' | 'RESTRICT' | 'NO ACTION'; export class ForeignKey { public readonly table: string; public readonly column: string; public readonly referencesTable: string; public readonly referencesColumn: string; public readonly onDelete: OnDeleteAction | null; public readonly onUpdate: OnDeleteAction | null; constructor( table: string, column: string, referencesTable: string, referencesColumn: string, onDelete: OnDeleteAction | null = null, onUpdate: OnDeleteAction | null = null ) { if (!table || table.trim().length === 0) { throw new Error('Foreign key table name cannot be empty'); } if (!column || column.trim().length === 0) { throw new Error('Foreign key column name cannot be empty'); } if (!referencesTable || referencesTable.trim().length === 0) { throw new Error('Referenced table name cannot be empty'); } if (!referencesColumn || referencesColumn.trim().length === 0) { throw new Error('Referenced column name cannot be empty'); } this.table = table.trim(); this.column = column.trim(); this.referencesTable = referencesTable.trim(); this.referencesColumn = referencesColumn.trim(); this.onDelete = onDelete; this.onUpdate = onUpdate; Object.freeze(this); } /** * Check if relationship is required (CASCADE or RESTRICT on delete) * * Semantic: CASCADE/RESTRICT implies required relationship */ isRequired(): boolean { return this.onDelete === 'CASCADE' || this.onDelete === 'RESTRICT'; } /** * Check if deletes cascade to child records */ cascadesOnDelete(): boolean { return this.onDelete === 'CASCADE'; } }