homework-jianmu/docs-en/13-operation/07-import.md

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---
title: Data Import
---
There are multiple ways of importing data provided by TDengine: import with script, import from data file, import using `taosdump`.
## Import Using Script
TDengine CLI `taos` supports `source <filename>` command for executing the SQL statements in the file in batch. The SQL statements for creating databases, creating tables, and inserting rows can be written in a single file with one statement on each line, then the file can be executed using the `source` command in TDengine CLI `taos` to execute the SQL statements in order and in batch. In the script file, any line beginning with "#" is treated as comments and ignored silently.
## Import from Data File
In TDengine CLI, data can be imported from a CSV file into an existing table. The data in a single CSV must belong to the same table and must be consistent with the schema of that table. The SQL statement is as below:
```sql
insert into tb1 file 'path/data.csv';
```
:::note
If there is a description in the first line of the CSV file, please remove it before importing. If there is no value for a column, please use `NULL` without quotes.
:::
For example, there is a subtable d1001 whose schema is as below:
```sql
taos> DESCRIBE d1001
Field | Type | Length | Note |
=================================================================================
ts | TIMESTAMP | 8 | |
current | FLOAT | 4 | |
voltage | INT | 4 | |
phase | FLOAT | 4 | |
location | BINARY | 64 | TAG |
groupid | INT | 4 | TAG |
```
The format of the CSV file to be imported, data.csv, is as below:
```csv
'2018-10-04 06:38:05.000',10.30000,219,0.31000
'2018-10-05 06:38:15.000',12.60000,218,0.33000
'2018-10-06 06:38:16.800',13.30000,221,0.32000
'2018-10-07 06:38:05.000',13.30000,219,0.33000
'2018-10-08 06:38:05.000',14.30000,219,0.34000
'2018-10-09 06:38:05.000',15.30000,219,0.35000
'2018-10-10 06:38:05.000',16.30000,219,0.31000
'2018-10-11 06:38:05.000',17.30000,219,0.32000
'2018-10-12 06:38:05.000',18.30000,219,0.31000
```
Then, the below SQL statement can be used to import data from file "data.csv", assuming the file is located under the home directory of the current Linux user.
```sql
taos> insert into d1001 file '~/data.csv';
Query OK, 9 row(s) affected (0.004763s)
```
## Import using taosdump
A convenient tool for importing and exporting data is provided by TDengine, `taosdump`, which can be used to export data from one TDengine cluster and import into another one. For the details of using `taosdump` please refer to [Tool for exporting and importing data: taosdump](/reference/taosdump).