---
title: REST API – Requests and Querying
description: "--- ## Query — Querying the Database This operation allows you to perform a SELECT query. The query must follow a specific format and has certain limitations: - Only one entity type per query (no JOIN) - Maximum 100 results…"
url: "https://www.kafinea.com/en/help/api/rest-api-requests-and-querying/"
updated: "2026-04-03"
category: API
---

# REST API – Requests and Querying

---

## Query — Querying the Database

This operation allows you to perform a SELECT query. The query must follow a specific format and has certain limitations:

- Only one entity type per query (no JOIN)
- Maximum 100 results per query (use `LIMIT` and `OFFSET` to paginate)
- The `WHERE`, `ORDER BY`, and `LIMIT` clauses are optional
- The query must be URL-encoded

> **GET** `https://apps.kafinea.com/{instance}/webservice.php`

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `operation` | string | yes | Must be `query` |
| `sessionName` | string | yes | Session identifier |
| `query` | string | yes | SQL query (URL-encoded) |

**curl example:**

```bash
curl "https://apps.kafinea.com/YourKafinea/webservice.php?operation=query&sessionName=YOUR_SESSION_ID&query=SELECT%20*%20FROM%20Contacts%20WHERE%20lastname%3D'Dupont'%20LIMIT%2010%20;"
```

### Query Format

```sql
SELECT * | ColumnsList | count(*)
FROM ModuleName
WHERE Conditions
ORDER BY ColumnsList
LIMIT Offset, Limit ;
```

> **Important:** the final semicolon is mandatory.

**Details:**

| Element | Description |
| --- | --- |
| `ColumnsList` | List of field names separated by commas |
| `ModuleName` | Entity module name |
| `Conditions` | Separated by `AND` or `OR`, processed from left to right. No grouping with parentheses. |
| `Offset` | Integer (optional) |
| `Limit` | Integer |

**Available condition types:**

| Type | Syntax | Example |
| --- | --- | --- |
| Operator | `<`, `>`, `<=`, `>=`, `!=`, `=` | `lastname = 'Dupont'` |
| IN | `IN(val1, val2, ...)` | `industry IN('Tech', 'Finance')` |
| LIKE | `LIKE 'pattern'` | `lastname LIKE '%dup%'` |

---

## Query Related — Querying Related Lists

This operation allows you to retrieve entities from the related lists of a specific entity. The query follows the same format as `query`, but **without a final semicolon**.

> **GET** `https://apps.kafinea.com/{instance}/webservice.php`

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `operation` | string | yes | Must be `query_related` |
| `sessionName` | string | yes | Session identifier |
| `id` | string | yes | Webservice ID of the parent entity |
| `relatedLabel` | string | yes | Related module name |
| `query` | string | yes | SQL query (URL-encoded, without final `;`) |

**curl example:**

```bash
curl "https://apps.kafinea.com/YourKafinea/webservice.php?operation=query_related&sessionName=YOUR_SESSION_ID&id=21x3456&relatedLabel=Documents&query=SELECT%20*%20FROM%20Documents%20WHERE%20filesize%20%3E%2010000"
```

**Query example:**

```sql
SELECT * FROM Documents WHERE filesize > 10000
```

---

## Related References 🔗

- [CRUD Operations](https://www.kafinea.com/en/documentation/api/rest-api-crud-operations/)
- [API Introduction](https://www.kafinea.com/en/documentation/api/rest-api-introduction/)