fix the bug that tiflash wrongly add padding for non-binary chars (#2088

)
pingcap · Jun 4, 2021 · 890c955 · 890c955
1 parent 0ed0a07
commit 890c955
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/dbms/src/Functions/FunctionsTiDBConversion.h b/dbms/src/Functions/FunctionsTiDBConversion.h
@@ -92,8 +92,10 @@ struct TiDBConvertToString
             col_null_map_to = ColumnUInt8::create(size, 0);
             vec_null_map_to = &col_null_map_to->getData();
         }
+        bool need_padding = tp.tp() == TiDB::TypeString && tp.flen() > 0 && tp.collate() == TiDB::ITiDBCollator::BINARY;
+
         String padding_string;
-        if (tp.tp() == TiDB::TypeString && tp.flen() > 0)
+        if (need_padding)
             padding_string.resize(tp.flen(), 0);
 
         const auto & col_with_type_and_name = block.getByPosition(arguments[0]);
@@ -132,7 +134,7 @@ struct TiDBConvertToString
                 if (byte_length < org_length)
                     context.getDAGContext()->handleTruncateError("Data Too Long");
                 write_buffer.write(reinterpret_cast<const char *>(&(*data_from)[current_offset]), byte_length);
-                if (tp.tp() == TiDB::TypeString && tp.flen() > 0 && byte_length < static_cast<size_t>(tp.flen()))
+                if (need_padding && byte_length < static_cast<size_t>(tp.flen()))
                     write_buffer.write(padding_string.data(), tp.flen() - byte_length);
                 writeChar(0, write_buffer);
                 offsets_to[i] = write_buffer.count();
@@ -162,7 +164,7 @@ struct TiDBConvertToString
                 if (byte_length < element_write_buffer.count())
                     context.getDAGContext()->handleTruncateError("Data Too Long");
                 write_buffer.write(reinterpret_cast<char *>(container_per_element.data()), byte_length);
-                if (tp.tp() == TiDB::TypeString && tp.flen() > 0 && byte_length < static_cast<size_t>(tp.flen()))
+                if (need_padding && byte_length < static_cast<size_t>(tp.flen()))
                     write_buffer.write(padding_string.data(), tp.flen() - byte_length);
                 writeChar(0, write_buffer);
                 offsets_to[i] = write_buffer.count();
@@ -205,7 +207,7 @@ struct TiDBConvertToString
                 if (byte_length < element_write_buffer.count())
                     context.getDAGContext()->handleTruncateError("Data Too Long");
                 write_buffer.write(reinterpret_cast<char *>(container_per_element.data()), byte_length);
-                if (tp.tp() == TiDB::TypeString && tp.flen() > 0 && byte_length < static_cast<size_t>(tp.flen()))
+                if (need_padding && byte_length < static_cast<size_t>(tp.flen()))
                     write_buffer.write(padding_string.data(), tp.flen() - byte_length);
                 writeChar(0, write_buffer);
                 offsets_to[i] = write_buffer.count();