---
title: "SQL-204: ProviderQueryProvider.GetProviderByTaxId"
summary: Read operation for `ProviderQueryProvider.GetProviderByTaxId`
status: draft
owner: SAIF.Core documentation team
last_reviewed: 2026-09-24
library: SAIF.Data
reference_type: package
---

# SQL-204: ProviderQueryProvider.GetProviderByTaxId

This statement is a read operation invoked through ORM (NHibernate LINQ). Executed by `ProviderQueryProvider.GetProviderByTaxId`.

## Classification

| Field | Value |
| --- | --- |
| **SQL ID** | SQL-204 |
| **Operation type** | Read |
| **Execution method** | ORM (NHibernate LINQ) |
| **Database** | Oracle* |
| **Schema** | [unqualified]** |
| **Command type** | N/A (ORM-generated) |
| **Business object** | `ProviderQueryProvider` |
| **Criteria property** | N/A — ORM |
| **Lifecycle method** | `GetProviderByTaxId` |

## Parameters

| Parameter | Direction | Type | Max length | Description |
| --- | --- | --- | --- | --- |
| `taxId` | Input | string | N/A | Method argument of `ProviderQueryProvider.GetProviderByTaxId` bound into the ORM expression; NHibernate generates the bind variable at runtime |

## Tables

| Table | Access | Columns used |
| --- | --- | --- |
| [PROVIDER](../database-tables.md#provider) | SELECT | PROVIDER_SEQ_NUM, UPDATE_NUM, PRIMARY_TAX_ID, UPDATE_DATE, UPDATE_USER (PRIMARY_TAX_ID also in COUNT filter) |

## LINQ statement

Source: `Data/SAIF.Data/Queries/Providers/ProviderQueryProvider.cs:61, 66`. The repository/queryable is initialised at `Data/SAIF.Data/Queries/Providers/ProviderQueryProvider.cs:27`.

```csharp
// Data/SAIF.Data/Queries/Providers/ProviderQueryProvider.cs:27
_providerRepository = Factory.GetRepository<Provider>().Query();

// Data/SAIF.Data/Queries/Providers/ProviderQueryProvider.cs:61
public Provider GetProviderByTaxId(string taxId, bool includeNonPrimaryTaxIds = false)
{
    var provider = new Provider();
    if (includeNonPrimaryTaxIds)
    {
        var providerTaxId = _providerTaxIdRepository.FirstOrDefault(pr => pr.TaxId == taxId);
        if (providerTaxId != null)
        {
            provider = _providerRepository.SingleOrDefault(pr => pr.Id == Convert.ToInt64(providerTaxId.Provider.Id));
        }
    }
    else
    {
        provider = _providerRepository.Count(pr => pr.PrimaryTaxId == taxId).Equals(0) ? new Provider() : _providerRepository.SingleOrDefault(pr => pr.PrimaryTaxId == taxId);
    }

    return provider;
}
```

## Sample SQL

> **Inferred SQL:** This SQL was inferred from the LINQ statement above and the NHibernate mappings. It is not concrete SQL from source code; NHibernate generates the executed statement at runtime, so aliases, column order, join syntax, and bind-parameter names may differ.

```sql
-- Inferred from LINQ (NHibernate mapping translation); not concrete SQL
-- Branch includeNonPrimaryTaxIds = true (line 61), after SQL-203 returns a row
SELECT
  P.PROVIDER_SEQ_NUM,
  P.UPDATE_NUM,
  P.PRIMARY_TAX_ID,
  P.UPDATE_DATE,
  P.UPDATE_USER
FROM PROVIDER P
WHERE P.PROVIDER_SEQ_NUM = :providerId;
-- SingleOrDefault: NHibernate expects at most one row

-- Branch includeNonPrimaryTaxIds = false (line 66), statement 1: Count
SELECT COUNT(*)
FROM PROVIDER P
WHERE P.PRIMARY_TAX_ID = :taxId;

-- Branch includeNonPrimaryTaxIds = false (line 66), statement 2: only when COUNT <> 0
SELECT
  P.PROVIDER_SEQ_NUM,
  P.UPDATE_NUM,
  P.PRIMARY_TAX_ID,
  P.UPDATE_DATE,
  P.UPDATE_USER
FROM PROVIDER P
WHERE P.PRIMARY_TAX_ID = :taxId
-- SingleOrDefault: NHibernate expects at most one row
```

Translation notes:
- `Convert.ToInt64(providerTaxId.Provider.Id)` touches only a materialized object (not the lambda parameter), so it is evaluated in memory and bound as `:providerId`. Reading `providerTaxId.Provider.Id` on the lazy proxy does not trigger a load, because the Id is known from the FK `PROVIDER_SEQ_NUM`.
- The `false` branch makes two round trips. If more than one provider shares a `PRIMARY_TAX_ID`, `SingleOrDefault` throws.

## Operations and processes

- [Provider queries](../operations/provider-queries.md)

## Business rules

- [SD-BR-080 Provider identity relationship and address code sets](../business-rules.md#sd-br-080-provider-identity-relationship-and-address-code-sets)
- [SD-BR-082 Dismissed bills excluded from provider location ids](../business-rules.md#sd-br-082-dismissed-bills-excluded-from-provider-location-ids)
- [SD-BR-083 Provider in MCO only within date window](../business-rules.md#sd-br-083-provider-in-mco-only-within-date-window)

## Sources
- `Data/SAIF.Data/Queries/Providers/ProviderQueryProvider.cs:61`