# mariadb

> Configures MariaDB connections, schema management, and game state queries for L2J server.
Use when: Setting up database connections, writing SQL queries, managing player/game data persistence, or troubleshooting database issues.

- Author: valeriybaranyshyn-pixel
- Repository: valeriybaranyshyn-pixel/Tales-of-Aden
- Version: 20260202145225
- Stars: 0
- Forks: 0
- Last Updated: 2026-02-06
- Source: https://github.com/valeriybaranyshyn-pixel/Tales-of-Aden
- Web: https://mule.run/skillshub/@@valeriybaranyshyn-pixel/Tales-of-Aden~mariadb:20260202145225

---

---
name: mariadb
description: |
  Configures MariaDB connections, schema management, and game state queries for L2J server.
  Use when: Setting up database connections, writing SQL queries, managing player/game data persistence, or troubleshooting database issues.
allowed-tools: Read, Edit, Write, Glob, Grep, Bash, mcp__context7__resolve-library-id, mcp__context7__query-docs
---

# MariaDB Skill

This L2J server uses MariaDB 10.4+/12.x with the `mariadb-java-client-3.1.4.jar` JDBC driver. Database access is centralized through `ConnectionPool.java` using `MariaDbPoolDataSource`. The schema contains 90+ tables covering player data, clans, events, and game state.

## Quick Start

### Get a Connection

```java
import net.sf.l2j.gameserver.ConnectionPool;

try (Connection con = ConnectionPool.getConnection();
     PreparedStatement ps = con.prepareStatement("SELECT * FROM characters WHERE obj_Id = ?"))
{
    ps.setInt(1, objectId);
    try (ResultSet rs = ps.executeQuery())
    {
        while (rs.next())
        {
            String name = rs.getString("char_name");
        }
    }
}
catch (SQLException e)
{
    LOGGER.error("Query failed", e);
}
```

### Connection URL Format

```properties
# Game Server (Files/game/config/server.properties)
URL = jdbc:mariadb://localhost:3306/toa3816?user=root&password=XXX&useUnicode=true&characterEncoding=utf-8&useSSL=false

# Login Server with pool settings (Files/auth/config/loginserver.properties)
URL = jdbc:mariadb://localhost:3306/toa3816?user=root&password=XXX&useUnicode=true&characterEncoding=utf-8&useSSL=false&maxPoolSize=80&minPoolSize=10&maxIdleTime=120&connectTimeout=5000
```

## Key Concepts

| Concept | Usage | Example |
|---------|-------|---------|
| ConnectionPool | Singleton factory for all DB access | `ConnectionPool.getConnection()` |
| try-with-resources | ALWAYS use for auto-close | `try (Connection con = ...)` |
| PreparedStatement | Parameterized queries (prevents SQL injection) | `ps.setInt(1, value)` |
| Batch operations | Bulk inserts/updates | `ps.addBatch(); ps.executeBatch()` |
| REPLACE INTO | Upsert pattern (insert or update) | `REPLACE INTO table (pk, val) VALUES (?, ?)` |

## Common Patterns

### Save Entity Pattern

```java
public void storeMe()
{
    try (Connection con = ConnectionPool.getConnection();
         PreparedStatement ps = con.prepareStatement("UPDATE characters SET level=?, exp=? WHERE obj_Id=?"))
    {
        ps.setInt(1, _level);
        ps.setLong(2, _exp);
        ps.setInt(3, _objectId);
        ps.executeUpdate();
    }
    catch (SQLException e)
    {
        _log.warning("Failed to save: " + e.getMessage());
    }
}
```

### Load Entity Pattern

```java
public void restoreMe()
{
    try (Connection con = ConnectionPool.getConnection();
         PreparedStatement ps = con.prepareStatement("SELECT * FROM characters WHERE obj_Id=?"))
    {
        ps.setInt(1, _objectId);
        try (ResultSet rs = ps.executeQuery())
        {
            if (rs.next())
            {
                _level = rs.getInt("level");
                _exp = rs.getLong("exp");
            }
        }
    }
    catch (SQLException e)
    {
        _log.warning("Failed to load: " + e.getMessage());
    }
}
```

## See Also

- [patterns](references/patterns.md) - Query patterns, batch operations, connection handling
- [workflows](references/workflows.md) - Schema changes, migrations, database setup

## Related Skills

- See the **database-schema** skill for table structures and relationships
- See the **configuration-management** skill for database URL configuration
- See the **java** skill for try-with-resources and exception handling

## Documentation Resources

> Fetch latest MariaDB documentation with Context7.

**How to use Context7:**
1. Use `mcp__context7__resolve-library-id` to search for "mariadb"
2. **Prefer website documentation** (IDs starting with `/websites/`) over source code repositories
3. Query with `mcp__context7__query-docs` using the resolved library ID

**Library ID:** `/mariadb-corporation/mariadb-docs`

**Recommended Queries:**
- "MariaDB Java JDBC prepared statements"
- "MariaDB connection pooling configuration"
- "MariaDB batch insert performance"