versioned_docs/version-3.0/sql-manual/sql-functions/table-valued-functions/query.md

---
{
  "title": "QUERY",
  "language": "en"
}
---

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## query

### Name

query

### description

Query table function (table-valued-function, tvf) can be used to transparently transmit query statements directly to a catalog for data query

:::info note
Supported by Doris version 2.1.3, currently only transparent query jdbc catalog is supported.
You need to create the corresponding catalog in Doris first.
:::

#### syntax

```sql
query(
  "catalog" = "catalog_name",
  "query" = "select * from db_name.table_name where condition"
  );
```

**Parameter Description**

Each parameter in the query table function tvf is a `"key"="value"` pair.
Related parameters:
- `catalog`: (required) catalog name, which needs to be filled in according to the name of the catalog.
- `query`: (required) The query statement to be executed.

### Example

Use the query function to query tables in the jdbc data source

```sql
select * from query("catalog" = "jdbc", "query" = "select * from db_name.table_name where condition");
```

Can be used with `desc function`

```sql
desc function query("catalog" = "jdbc", "query" = "select * from db_name.table_name where condition");
```

### Keywords

    query, table-valued-function, tvf

### Best Prac

Transparent query for tables in jdbc catalog data source

```sql
select * from query("catalog" = "jdbc", "query" = "select * from test.student");
+------+---------+
| id   | name    |
+------+---------+
| 1    | alice   |
| 2    | bob     |
| 3    | jack    |
+------+---------+
select * from query("catalog" = "jdbc", "query" = "select * from test.score");
+------+---------+
| id   | score   |
+------+---------+
| 1    | 100     |
| 2    | 90      |
| 3    | 80      |
+------+---------+
```

Transparent join query for tables in jdbc catalog data source

```sql
select * from query("catalog" = "jdbc", "query" = "select a.id, a.name, b.score from test.student a join test.score b on a.id = b.id");
+------+---------+---------+
| id   | name    | score   |
+------+---------+---------+
| 1    | alice   | 100     |
| 2    | bob     | 90      |
| 3    | jack    | 80      |
+------+---------+---------+
```