11-escape.md 1.4 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
---
title: Escape Characters
---

Below table is the list of escape characters used in TDengine.

| 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 |

:::note
Escape characters are available from version 2.4.0.4 .

:::

## 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 "\_".