---
title: "SQL-016: Detect duplicate active email"
summary: Checks for an existing active non-test user with the given email address.
status: draft
owner: <owner>
last_reviewed: 2026-07-24
library: SAIF.Business.External.Users
reference_type: package
---

# SQL-016: Detect duplicate active email

Queries `EXT_USER`, `EMAIL_ADDRESS`, and `EXT_USER_TYPE` to detect whether an active, non-deleted, non-test user already exists with the given email address. Used to enforce [BR-EU-04](../business-rules.md#br-eu-04-unique-active-email-per-non-test-user).

## Classification

| Field | Value |
| --- | --- |
| **SQL ID** | SQL-016 |
| **Operation type** | Read |
| **Execution method** | Inline SQL |
| **Database** | Oracle |
| **Schema** | [unqualified]** |
| **Command type** | Text |
| **Business object** | `clsUser` |
| **Criteria property** | Local SQL |
| **Lifecycle method** | Validation logic |

## Parameters

| Parameter | Direction | Type | Max length | Description |
| --- | --- | --- | --- | --- |
| `:Email` | Input | String | 100 | Email address to check for duplicates. |

## Tables

| Table | Access | Columns used |
| --- | --- | --- |
| [EXT_USER](../database-tables.md#ext_user) | SELECT | `ACTIVE_DIRECTORY_ID`, `TEST_USER_FLAG`, `STATUS_CODE`, `EMAIL_ADDRESS_SEQ_NUM` |
| [EMAIL_ADDRESS](../database-tables.md#email_address) | JOIN | `EMAIL_ADDRESS_SEQ_NUM`, `EMAIL_ADDRESS` |
| [EXT_USER_TYPE](../database-tables.md#ext_user_type) | JOIN | `EXT_USER_SEQ_NUM`, `EXT_USER_TYPE_CODE`, `CUSTOMER_ID`, `CUSTOMER_GROUP_ID` |

## Sample SQL

```sql
SELECT
    u.active_directory_id,
    e.email_address,
    t.ext_user_type_code,
    UPPER(t.customer_id) AS customer_id,
    UPPER(t.customer_group_id) AS customer_group_id
FROM ext_user u
JOIN email_address e ON e.email_address_seq_num = u.email_address_seq_num
JOIN ext_user_type t ON t.ext_user_seq_num = u.ext_user_seq_num
WHERE u.test_user_flag = 'N'
  AND u.status_code <> 'DEL'
  AND LOWER(email_address) = :Email
```

## Operations and processes
- [User self-registration / account management](../operations/user-account-management.md)

## Business rules
- [BR-EU-04: Unique active email per non-test user](../business-rules.md#br-eu-04-unique-active-email-per-non-test-user)

> **Note:** Statements marked with `*` were inferred from code structure, naming conventions, or contextual evidence where direct confirmation was not available in source artifacts. Statements marked with `**` could not be confirmed; treat as unknown until verified.

## Sources
- `Business\SAIF.Business.External.Users\clsUser.vb`