增加翻译缓存

prisma/migrations/20260106105236_create_translation_history/migration.sql

@@ -0,0 +1,30 @@
+-- CreateTable
+CREATE TABLE "translation_history" (
+    "id" SERIAL NOT NULL,
+    "user_id" TEXT,
+    "source_text" TEXT NOT NULL,
+    "source_language" VARCHAR(20) NOT NULL,
+    "target_language" VARCHAR(20) NOT NULL,
+    "translated_text" TEXT NOT NULL,
+    "source_ipa" TEXT,
+    "target_ipa" TEXT,
+    "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updated_at" TIMESTAMP(3) NOT NULL,
+
+    CONSTRAINT "translation_history_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "translation_history_user_id_idx" ON "translation_history"("user_id");
+
+-- CreateIndex
+CREATE INDEX "translation_history_created_at_idx" ON "translation_history"("created_at");
+
+-- CreateIndex
+CREATE INDEX "translation_history_source_text_target_language_idx" ON "translation_history"("source_text", "target_language");
+
+-- CreateIndex
+CREATE INDEX "translation_history_translated_text_source_language_target__idx" ON "translation_history"("translated_text", "source_language", "target_language");
+
+-- AddForeignKey
+ALTER TABLE "translation_history" ADD CONSTRAINT "translation_history_user_id_fkey" FOREIGN KEY ("user_id") REFERENCES "user"("id") ON DELETE SET NULL ON UPDATE CASCADE;