---
title: Missing core Database Constraint
slug: '2158'
canonical_url: https://docs.coveo.com/en/2158/
collection: coveo-for-sitecore-v5
source_format: adoc
---
# Missing core Database Constraint
## Description

When calling `\http://<INSTANCE_HOSTNAME>/coveo/rest`, you get this error:

`Cannot insert the value NULL into column 'ID', table '<INSTANCE_HOSTNAME>_core.dbo.Properties';
column doesn't allow nulls.
INSERT fails.`

You also get the same result if you open the database `<INSTANCE_HOSTNAME>_core` in SQL Studio and perform this query:

```sql
INSERT INTO [dbo].[properties] ([dbo].[key], [dbo].[value]) VALUES ('TestKey', 'Test Value')
```

## Explanation

There's a constraint missing in the `dbo.Properties` table of `<INSTANCE_HOSTNAME>_core` database.

## Resolution

Recreate the constraints in your Sitecore database.
The simplest way is to run the following query in your `<INSTANCE_HOSTNAME>_core` database:

```sql
USE [<INSTANCE_HOSTNAME>_core]
​
GO
​
ALTER TABLE [dbo].[Properties] ADD CONSTRAINT [DF_Properties_ID] DEFAULT (newid()) FOR [ID]
​
GO
```

Where you replace `[<INSTANCE_HOSTNAME>_core]` with the name of your `core` database.