-- CreateTable
CREATE TABLE "PurchaseOrderRevision" (
    "id" TEXT NOT NULL PRIMARY KEY,
    "purchaseOrderId" TEXT NOT NULL,
    "revisionNumber" INTEGER NOT NULL,
    "reason" TEXT NOT NULL,
    "snapshot" TEXT NOT NULL,
    "createdById" TEXT,
    "createdAt" DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "updatedAt" DATETIME NOT NULL,
    CONSTRAINT "PurchaseOrderRevision_purchaseOrderId_fkey" FOREIGN KEY ("purchaseOrderId") REFERENCES "PurchaseOrder" ("id") ON DELETE CASCADE ON UPDATE CASCADE,
    CONSTRAINT "PurchaseOrderRevision_createdById_fkey" FOREIGN KEY ("createdById") REFERENCES "User" ("id") ON DELETE SET NULL ON UPDATE CASCADE
);

-- CreateIndex
CREATE UNIQUE INDEX "PurchaseOrderRevision_purchaseOrderId_revisionNumber_key" ON "PurchaseOrderRevision"("purchaseOrderId", "revisionNumber");

-- CreateIndex
CREATE INDEX "PurchaseOrderRevision_purchaseOrderId_createdAt_idx" ON "PurchaseOrderRevision"("purchaseOrderId", "createdAt");