feat(editor): preview dml changes as readonly select

apps/desktop/src/lib/backend/api.ts

@@ -272,6 +272,7 @@ export const prepareDataGridSave = forward("prepareDataGridSave");
 export const extractDataGridSelection = forward("extractDataGridSelection");
 export const buildDataGridCopyUpdateStatements = forward("buildDataGridCopyUpdateStatements");
 export const buildDataGridCopyInsertStatement = forward("buildDataGridCopyInsertStatement");
+export const buildDmlChangePreviewSql = forward("buildDmlChangePreviewSql");
 export const buildDataGridContextFilterCondition = forward("buildDataGridContextFilterCondition");
 export const buildDataGridColumnValueFilterCondition = forward("buildDataGridColumnValueFilterCondition");
 export const buildDataGridColumnValuesFilterCondition = forward("buildDataGridColumnValuesFilterCondition");

apps/desktop/src/lib/backend/http.ts

@@ -165,6 +165,7 @@ import type {
   DataGridSaveStatementOptions,
   HiveTablePropertiesSqlOptions,
 } from "@/lib/dataGrid/dataGridSql";
+import type { DmlChangePreviewSqlOptions, DmlChangePreviewSqlResult } from "@/lib/sql/dmlChangePreview";
 import type { DataGridExtractRequest, DataGridExtractResult } from "@/lib/dataGrid/dataGridCopyExtractor";
 import type { BuildTableOwnerChangeSqlOptions, BuildTableStructureChangeSqlOptions, BuildSingleColumnAlterSqlOptions, SqliteTableStructureChangePreview, TableStructureChangeSql } from "@/lib/table/tableStructureEditorSql";
 import type { BuildTableSelectSqlOptions } from "@/lib/table/tableSelectSql";
@@ -1527,6 +1528,10 @@ export async function buildDataGridCopyInsertStatement(options: DataGridCopyInse
   return result ?? undefined;
 }
 
+export async function buildDmlChangePreviewSql(options: DmlChangePreviewSqlOptions): Promise<DmlChangePreviewSqlResult> {
+  return post("/api/query/build-dml-change-preview-sql", { options });
+}
+
 export async function buildDataGridContextFilterCondition(options: DataGridContextFilterConditionOptions): Promise<string | undefined> {
   const result = await post<string | null>("/api/query/build-data-grid-context-filter-condition", { options });
   return result ?? undefined;

apps/desktop/src/lib/backend/tauri.ts

@@ -84,6 +84,7 @@ import type {
   DataGridSaveStatementOptions,
   HiveTablePropertiesSqlOptions,
 } from "@/lib/dataGrid/dataGridSql";
+import type { DmlChangePreviewSqlOptions, DmlChangePreviewSqlResult } from "@/lib/sql/dmlChangePreview";
 import type { DataGridExtractRequest, DataGridExtractResult } from "@/lib/dataGrid/dataGridCopyExtractor";
 import type { DataCompareFromTablesOptions, DataCompareFromTablesPreparation, DataCompareSyncPlan, DataCompareSyncPlanOptions, DataComparePreparation, DataComparePreparationOptions } from "@/lib/dataGrid/dataCompare";
 import type { SchemaDiffPreparation, SchemaDiffPreparationOptions, SchemaSyncSqlPlan, SelectedSchemaDiffInput, GenerateSchemaSyncPlanOptions, TableDiff, FunctionDiff, SequenceDiff, RuleDiff, OwnerDiff } from "@/lib/schema/schemaDiff";
@@ -1827,6 +1828,10 @@ export async function buildDataGridContextFilterCondition(options: DataGridConte
   return result ?? undefined;
 }
 
+export async function buildDmlChangePreviewSql(options: DmlChangePreviewSqlOptions): Promise<DmlChangePreviewSqlResult> {
+  return invoke("build_dml_change_preview_sql", { options });
+}
+
 export async function buildDataGridColumnValueFilterCondition(options: DataGridColumnValueFilterConditionOptions): Promise<string | undefined> {
   const result = await invoke<string | null>("build_data_grid_column_value_filter_condition", { options });
   return result ?? undefined;

apps/desktop/src/lib/sql/__tests__/dmlChangePreview.spec.ts

@@ -0,0 +1,20 @@
+import { describe, expect, it } from "vitest";
+import { looksLikeDmlStatement } from "../dmlChangePreview";
+
+describe("looksLikeDmlStatement", () => {
+  it("recognizes UPDATE / INSERT / DELETE statements", () => {
+    expect(looksLikeDmlStatement("UPDATE admin_sessions SET public_id = 123 WHERE id = 1")).toBe(true);
+    expect(looksLikeDmlStatement("  INSERT INTO t (a) VALUES (1)")).toBe(true);
+    expect(looksLikeDmlStatement("\nDELETE FROM t WHERE id = 2")).toBe(true);
+  });
+  it("ignores leading whitespace and preserves case-insensitivity", () => {
+    expect(looksLikeDmlStatement("   update t set a = 1")).toBe(true);
+    expect(looksLikeDmlStatement("Insert into t values (1)")).toBe(true);
+  });
+  it("rejects non-DML and unrelated statements", () => {
+    expect(looksLikeDmlStatement("SELECT * FROM t")).toBe(false);
+    expect(looksLikeDmlStatement("WITH x AS (SELECT 1) SELECT * FROM x")).toBe(false);
+    expect(looksLikeDmlStatement("")).toBe(false);
+    expect(looksLikeDmlStatement("CREATE TABLE t (a int)")).toBe(false);
+  });
+});

apps/desktop/src/lib/sql/dmlChangePreview.ts

@@ -0,0 +1,37 @@
+/** 「预览变更」请求/响应的前端类型（对应后端 dml_preview_sql）。 */
+
+export interface DmlChangePreviewSqlOptions {
+  /** 用户写的一条 DML 语句（通常是当前语句）。 */
+  sql: string;
+  /** 连接类型（决定解析方言 / 默认标识符引号）。 */
+  databaseType?: string;
+  /** 连接的标识符引号字符（如 `"`、`` ` ``、`[`）。 */
+  identifierQuote?: string;
+  /** 目标表的列（ordinal）。提供且为单表 UPDATE 时，新值列紧跟其原值列。 */
+  columns?: string[];
+}
+
+export interface DmlChangePreviewTableRef {
+  catalog?: string;
+  database?: string;
+  schema?: string;
+  table?: string;
+}
+
+export interface DmlChangePreviewSqlResult {
+  /** 生成的只读 SELECT：在结果网格展示受影响行 + 「新值」列。 */
+  sql: string;
+  /** 语句类型：update / insert / delete。 */
+  operation: string;
+  /** 是否有「新值」列（仅 UPDATE 有）。 */
+  hasNewValueColumns: boolean;
+  /** 语句目标表引用（供前端拉取列元数据以交错展示新值列）。 */
+  tables: DmlChangePreviewTableRef[];
+}
+
+/** 从 SQL 文本粗略识别是否为可预览的 DML（用于「预览变更」入口显隐）。 */
+const DML_PREVIEW_RE = /^\s*(update|insert|delete)\b/i;
+
+export function looksLikeDmlStatement(sql: string): boolean {
+  return DML_PREVIEW_RE.test(sql);
+}