feat(grid): preview text stored in MySQL BLOB cells

apps/desktop/src/lib/dataGrid/binaryCellDownload.ts

@@ -114,6 +114,7 @@ const HEX_ESCAPE_RE = /^(?:\\x[0-9a-fA-F]{2}|\s)+$/;
 const BINARY_TYPE_RE = /^(?:blob|tinyblob|mediumblob|longblob|bytea|bytes|binary|varbinary|image|raw|long\s+raw)(?:\b|\()/i;
 const FIXED_BINARY_TYPE_RE = /^binary(?:\b|\()/i;
 const BINARY_STRING_TYPE_RE = /^(?:binary|varbinary)(?:\b|\()/i;
+const BLOB_TYPE_RE = /^(?:blob|tinyblob|mediumblob|longblob)(?:\b|\()/i;
 const MYSQL_FILE_IMPORT_TYPE_RE = /^(?:blob|tinyblob|mediumblob|longblob|binary|varbinary)(?:\b|\()/i;
 
 function copyBytesForBlob(bytes: Uint8Array): Uint8Array<ArrayBuffer> {
@@ -182,6 +183,11 @@ export function isBinaryCellColumnType(columnType?: string): boolean {
   return !!type && BINARY_TYPE_RE.test(type);
 }
 
+export function isBlobCellColumnType(columnType?: string): boolean {
+  const type = (columnType ?? "").trim();
+  return !!type && BLOB_TYPE_RE.test(type);
+}
+
 export function canImportBinaryCellFile(databaseType?: DatabaseType, columnType?: string): boolean {
   const type = (columnType ?? "").trim();
   if (databaseType === "postgres") return /^bytea(?:\b|\()/i.test(type);
@@ -200,14 +206,34 @@ export function binaryCellDisplayText(value: unknown, columnType?: string, origi
   }
   const bytes = parseBinaryCellBytes(value, columnType, databaseType);
   if (!bytes || !isBinaryCellColumnType(columnType)) return null;
-  if (BINARY_STRING_TYPE_RE.test((columnType ?? "").trim())) {
-    const previewBytes = FIXED_BINARY_TYPE_RE.test((columnType ?? "").trim()) ? trimTrailingNullBytes(bytes) : bytes;
-    const text = printableUtf8Text(previewBytes);
+  if (isBinaryCellTextPreviewColumn(columnType, databaseType)) {
+    const text = binaryCellUtf8TextBytes(bytes, columnType);
     if (text !== null) return text;
   }
   return `${binaryCellDisplayLabel(columnType)} [${formatBinaryCellByteSize(bytes.length)}]`;
 }
 
+export function binaryCellUtf8Text(value: unknown, columnType?: string, databaseType?: DatabaseType): string | null {
+  if (!isBinaryCellColumnType(columnType) || !isBinaryCellTextPreviewColumn(columnType, databaseType)) return null;
+  const bytes = parseBinaryCellBytes(value, columnType, databaseType);
+  if (!bytes) return null;
+  return binaryCellUtf8TextBytes(bytes, columnType);
+}
+
+// MySQL BLOB 的文本预览必须与编辑写回路径（coerceMysqlBlobTextValue，仅 mysql）走同一闸门：
+// SQLite/DuckDB/H2/Firebird 等库同样暴露 `blob` 列，若一律按文本预览会出现
+// “显示是文本、编辑器却是十六进制”的不一致，故 blob 文本预览仅在 mysql 连接开启。
+// binary/varbinary 的文本预览早于该特性存在（如 TDengine BINARY 文本），保持全库通用。
+function isBinaryCellTextPreviewColumn(columnType: string | undefined, databaseType: DatabaseType | undefined): boolean {
+  if (BINARY_STRING_TYPE_RE.test((columnType ?? "").trim())) return true;
+  return isBlobCellColumnType(columnType) && databaseType === "mysql";
+}
+
+function binaryCellUtf8TextBytes(bytes: Uint8Array, columnType?: string): string | null {
+  const previewBytes = FIXED_BINARY_TYPE_RE.test((columnType ?? "").trim()) ? trimTrailingNullBytes(bytes) : bytes;
+  return printableUtf8Text(previewBytes);
+}
+
 function trimTrailingNullBytes(bytes: Uint8Array): Uint8Array {
   let end = bytes.length;
   while (end > 0 && bytes[end - 1] === 0) end--;

apps/desktop/src/lib/dataGrid/dataGridCellCoercion.ts

@@ -1,5 +1,6 @@
 import type { GridCellValue } from "@/lib/dataGrid/dataGridSql";
 import type { DatabaseType, ColumnInfo } from "@/types/database";
+import { binaryCellBytesToHexValue, binaryCellUtf8Text, isBlobCellColumnType } from "@/lib/dataGrid/binaryCellDownload";
 import { isNumericColumnType } from "@/lib/dataGrid/dataGridColumnType";
 import { isBooleanColumnType } from "@/lib/dataGrid/dataGridBooleanColumn";
 
@@ -17,6 +18,8 @@ export function coerceDataGridCellValue(options: CoerceDataGridCellValueOptions)
   const { value, oldValue } = options;
   if (value === "" && options.emptyStringAsNull) return null;
   if (value === "" && oldValue === null && !options.preserveEmptyString) return null;
+  const blobValue = coerceMysqlBlobTextValue(options);
+  if (blobValue !== undefined) return blobValue;
   const postgresArrayValue = coercePostgresArrayValue(options);
   if (postgresArrayValue !== undefined) return postgresArrayValue;
   // Excel-pasted values often carry thousands separators (10,000.00) that make
@@ -68,12 +71,24 @@ function parseBooleanInput(value: string, allowNumericAliases: boolean): boolean
 export function dataGridCellEditorText(options: { value: GridCellValue | undefined; databaseType: DatabaseType | undefined; columnInfo: Pick<ColumnInfo, "data_type"> | undefined }): string {
   const value = options.value ?? null;
   if (value === null) return "";
+  if (options.databaseType === "mysql" && isBlobCellColumnType(options.columnInfo?.data_type)) {
+    const text = binaryCellUtf8Text(value, options.columnInfo?.data_type, options.databaseType);
+    if (text !== null) return text;
+  }
   if (Array.isArray(value) && options.databaseType === "postgres" && isPostgresArrayColumn(options.columnInfo, value)) {
     return formatPostgresArrayText(value);
   }
   return typeof value === "object" ? JSON.stringify(value) : String(value);
 }
 
+function coerceMysqlBlobTextValue(options: CoerceDataGridCellValueOptions): GridCellValue | undefined {
+  if (options.databaseType !== "mysql" || !isBlobCellColumnType(options.columnInfo?.data_type)) return undefined;
+  const originalText = binaryCellUtf8Text(options.oldValue, options.columnInfo?.data_type, options.databaseType);
+  if (originalText === null) return undefined;
+  if (options.value === originalText) return options.oldValue;
+  return binaryCellBytesToHexValue(new TextEncoder().encode(options.value));
+}
+
 export function dataGridCellDisplayText(options: { value: GridCellValue; databaseType: DatabaseType | undefined; columnInfo: Pick<ColumnInfo, "data_type"> | undefined }): string | undefined {
   if (Array.isArray(options.value) && options.databaseType === "postgres" && isPostgresArrayColumn(options.columnInfo, options.value)) {
     return formatPostgresArrayText(options.value);