Amazon Redshift will no longer support the creation of new Python UDFs starting Patch 198. Existing Python UDFs will continue to function until June 30, 2026. For more information, see the [ blog post ](https://aws.amazon.com/blogs/big-data/amazon-redshift-python-user-defined-functions-will-reach-end-of-support-after-june-30-2026/). 

# STL\_LIMIT
<a name="r_STL_LIMIT"></a>

Analyzes the execution steps that occur when a LIMIT clause is used in a SELECT query.

STL\_LIMIT is visible to all users. Superusers can see all rows; regular users can see only their own data. For more information, see [Visibility of data in system tables and views](cm_chap_system-tables.md#c_visibility-of-data).

**Note**  
STL\_LIMIT only contains queries run on main provisioned clusters. It doesn't contain queries run on concurrency scaling clusters or on serverless namespaces. To access explain plans for queries run on both main clusters, concurrency scaling clusters, and serverless namespaces, we recommend that you use the SYS monitoring view [SYS\_QUERY\_DETAIL](SYS_QUERY_DETAIL.md) . The data in the SYS monitoring view is formatted to be easier to use and understand.

## Table columns
<a name="r_STL_LIMIT-table-columns"></a>


| Column name  | Data type  | Description  | 
| --- | --- | --- | 
| userid | integer | ID of the user who generated the entry. | 
| query | integer | Query ID. The query column can be used to join other system tables and views. | 
| slice | integer | Number that identifies the slice where the query was running. | 
| segment | integer | Number that identifies the query segment. | 
| step | integer | Query step that ran. | 
| starttime | timestamp | Time in UTC that the query started. Total time includes queuing and execution. with 6 digits of precision for fractional seconds. For example: 2009-06-12 11:29:19.131358. | 
| endtime | timestamp | Time in UTC that the query finished. Total time includes queuing and execution. with 6 digits of precision for fractional seconds. For example: 2009-06-12 11:29:19.131358. | 
| tasknum | integer | Number of the query task process that was assigned to run the step. | 
| rows | bigint | Total number of rows that were processed. | 
| checksum | bigint | This information is for internal use only. | 

## Sample queries
<a name="r_STL_LIMIT-sample-queries"></a>

In order to generate a row in STL\_LIMIT, this example first runs the following query against the VENUE table using the LIMIT clause. 

```
select * from venue
order by 1
limit 10;
```

```
 venueid |         venuename          |    venuecity    | venuestate | venueseats
---------+----------------------------+-----------------+------------+------------
       1 | Toyota Park                | Bridgeview      | IL         |          0
       2 | Columbus Crew Stadium      | Columbus        | OH         |          0
       3 | RFK Stadium                | Washington      | DC         |          0
       4 | CommunityAmerica Ballpark  | Kansas City     | KS         |          0
       5 | Gillette Stadium           | Foxborough      | MA         |      68756
       6 | New York Giants Stadium    | East Rutherford | NJ         |      80242
       7 | BMO Field                  | Toronto         | ON         |          0
       8 | The Home Depot Center      | Carson          | CA         |          0
       9 | Dick's Sporting Goods Park | Commerce City   | CO         |          0
      10 | Pizza Hut Park             | Frisco          | TX         |          0
(10 rows)
```

Next, run the following query to find the query ID of the last query you ran against the VENUE table. 

```
select max(query)
from stl_query;
```

```
  max
--------
 127128
(1 row)
```

Optionally, you can run the following query to verify that the query ID corresponds to the LIMIT query you previously ran. 

```
select query, trim(querytxt)
from stl_query
where query=127128;
```

```
 query  |                  btrim
--------+------------------------------------------
 127128 | select * from venue order by 1 limit 10;
(1 row)
```

Finally, run the following query to return information about the LIMIT query from the STL\_LIMIT table. 

```
select slice, segment, step, starttime, endtime, tasknum
from stl_limit
where query=127128
order by starttime, endtime;
```

```
  slice | segment | step |         starttime          |          endtime           | tasknum
 -------+---------+------+----------------------------+----------------------------+---------
      1 |       1 |    3 | 2013-09-06 22:56:43.608114 | 2013-09-06 22:56:43.609383 |      15
      0 |       1 |    3 | 2013-09-06 22:56:43.608708 | 2013-09-06 22:56:43.609521 |      15
  10000 |       2 |    2 | 2013-09-06 22:56:43.612506 | 2013-09-06 22:56:43.612668 |       0
(3 rows)
```