versioned_docs/version-2.1/sql-manual/sql-functions/table-valued-functions/query.md

---
{
    "title": "QUERY",
    "language": "en",
    "description": "Query table function (table-valued-function, tvf) can be used to transparently transmit query statements directly to a catalog for data query"
}
---

## Description

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

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>", 
    "query" = "<query_sql>"
  );
```

## Required Parameters
Each parameter in the query table function tvf is a `"key"="value"` pair.

| Field      | Description                                |
|------------|--------------------------------------------|
| `catalog`  | Catalog name, which needs to be filled in according to the name of the catalog. |
| `query`    | The query statement to be executed.       |


## Examples

Can be used with `desc function`

```sql
desc function query("catalog" = "jdbc", "query" = "select * from test.student");
```
```text
+-------+------+------+-------+---------+-------+
| Field | Type | Null | Key   | Default | Extra |
+-------+------+------+-------+---------+-------+
| id    | int  | Yes  | true  | NULL    |       |
| name  | text | Yes  | false | NULL    | NONE  |
+-------+------+------+-------+---------+-------+
```

Transparent query for tables in jdbc catalog data source

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