docs-v2/content/flux/v0/query-data/sql/postgresql.md

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---
title: Query PostgreSQL
list_title: PostgreSQL
description: >
Use [`sql.from()`](/flux/v0/stdlib/sql/from/) with the `postgres` driver to query PostgreSQL.
menu:
flux_v0:
name: PostgreSQL
parent: SQL databases
weight: 101
related:
- /flux/v0/stdlib/sql/from/
list_code_example: |
```js
import "sql"
sql.from(
driverName: "postgres",
dataSourceName: "postgresql://username:password@localhost:5432",
query: "SELECT * FROM example_table",
)
```
---
To query [PostgreSQL](https://www.postgresql.org/) with Flux:
1. Import the [`sql` package](/flux/v0/stdlib/sql/).
2. Use [`sql.from()`](/flux/v0/stdlib/sql/from/) and provide the following parameters:
- **driverName**: postgres
- **dataSourceName**: _See [data source name](#postgresql-data-source-name)_
- **query**: PSQL query to execute
```js
import "sql"
sql.from(
driverName: "postgres",
dataSourceName: "postgresql://username:password@localhost:5432",
query: "SELECT * FROM example_table",
)
```
---
## PostgreSQL data source name
The `postgres` driver uses the following DSN syntax (also known as a **connection string**):
```
postgres://username:password@localhost:5432/dbname?param=value
```
## PostgreSQL to Flux data type conversion
`sql.from()` converts PostgreSQL data types to Flux data types.
| PostgreSQL data type | Flux data type |
| :-------------------------------------------------------------------------- | :-------------------------------------------- |
| INT, BIGINT, SMALLINT, TINYINT, INT2, INT4, INT8, SERIAL2, SERIAL4, SERIAL8 | [int](/flux/v0/data-types/basic/int/) |
| FLOAT4, FLOAT8 | [float](/flux/v0/data-types/basic/float/) |
| DATE, TIME, TIMESTAMP | [time](/flux/v0/data-types/basic/time/) |
| BOOL | [bool](/flux/v0/data-types/basic/bool/) |
| TEXT | [string](/flux/v0/data-types/basic/string/) |
{{% caption %}}
All other PostgreSQL data types are converted to strings.
{{% /caption %}}