{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[21:22] hl[21:22] *}

### Create a Session Dependency { #create-a-session-dependency }

A **`Session`** is what stores the **objects in memory** and keeps track of any changes needed in the data, then it **uses the `engine`** to communicate with the database.

import jakarta.annotation.PostConstruct;

/**
 * Helper class for managing popular words and suggestions.
 * Provides functionality to retrieve popular words based on search parameters
 * and manages caching for improved performance.
 */
public class PopularWordHelper {
    /** Logger instance for this class */
    private static final Logger logger = LogManager.getLogger(PopularWordHelper.class);

   */
  protected void startUp() throws Exception {}

  /**
   * Run the service. This method is invoked on the execution thread. Implementations must respond
   * to stop requests. You could poll for lifecycle changes in a work loop:
   *
   * <pre>
   *   public void run() {
   *     while ({@link #isRunning()}) {
   *       // perform a unit of work
   *     }
   *   }
   * </pre>
   *

	}

	return tx
}

// Commit commits the changes in a transaction
func (db *DB) Commit() *DB {
	if committer, ok := db.Statement.ConnPool.(TxCommitter); ok && committer != nil && !reflect.ValueOf(committer).IsNil() {
		db.AddError(committer.Commit())
	} else {
		db.AddError(ErrInvalidTransaction)
	}
	return db
}

// Rollback rollbacks the changes in a transaction
func (db *DB) Rollback() *DB {

   * calling {@code get(columnKey, rowKey)} on the generated table always returns the same value as
   * calling {@code get(rowKey, columnKey)} on the original table. Updating the original table
   * changes the contents of the transposed table and vice versa.
   *
   * <p>The returned table supports update operations as long as the input table supports the

## 2. Protocol Specification Reference

- **MS-SMB2 Section 2.2.13.2.12**: SMB2_CREATE_REQUEST_LEASE_V2 for directories
- **MS-SMB2 Section 2.2.14.2.12**: SMB2_CREATE_RESPONSE_LEASE_V2 for directories  

##### Synthetic headers have changed

Previously OkHttp added a synthetic response header, `OkHttp-Selected-Transport`. It
has been replaced with a new synthetic header, `OkHttp-Selected-Protocol`.

##### Changes

 * New: Support for `HTTP-draft-09/2.0`.
 * New: Support for `spdy/3.1`. Dropped support for `spdy/3`.
 * New: Use ALPN on Android platforms that support it (4.4+)
 * New: CacheControl model and parser.

        this.allRecordCount = allRecordCount;
    }

    /**
     * Gets the total number of pages.
     *
     * @return the total page count
     */
    public int getAllPageCount() {
        return allPageCount;
    }

    /**
     * Sets the total number of pages.
     *
     * @param allPageCount the total page count
     */

Em particular, isso pode ser uma boa alternativa para uma lógica em um middleware

Por exemplo, se você quiser ler ou manipular o corpo da requisição antes que ele seja processado pela sua aplicação.

/// danger | Perigo

Isso é um recurso "avançado".

Se você for um iniciante em **FastAPI** você deve considerar pular essa seção.

///

## Casos de Uso

Alguns casos de uso incluem:

             <b>fastapi run</b>

             Logs:

     <span style="background-color:#007166"><font color="#D3D7CF"> INFO </font></span>  Will watch for changes in these directories:
             <b>[</b><font color="#4E9A06">&apos;/home/user/code/awesomeapp&apos;</font><b>]</b>