homework-jianmu/docs/en/12-taos-sql/18-escape.md

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---
title: Escape Characters
description: This document describes the usage of escape characters in TDengine.
---
## Escape Characters
| Escape Character | **Actual Meaning** |
| :--------------: | ------------------------ |
| `\'` | Single quote ' |
| `\"` | Double quote " |
| \n | Line Break |
| \r | Carriage Return |
| \t | tab |
| `\\` | Back Slash \ |
| `\%` | % see below for details |
| `\_` | \_ see below for details |
## Restrictions
1. If there are escape characters in identifiers (database name, table name, column name)
- Identifier without ``: Error will be returned because identifier must be constituted of digits, ASCII characters or underscore and can't be started with digits
- Identifier quoted with ``: Original content is kept, no escaping
2. If there are escape characters in values
- The escape characters will be escaped as the above table. If the escape character doesn't match any supported one, the escape character "\" will be ignored.
- "%" and "\_" are used as wildcards in `like`. `\%` and `\_` should be used to represent literal "%" and "\_" in `like`,. If `\%` and `\_` are used out of `like` context, the evaluation result is "`\%`"and "`\_`", instead of "%" and "\_".