通过创建仅专用于与数据库交互（获取用户或项目）的函数，独立于*路径操作函数*，您可以更轻松地在多个部分中重用它们，并为它们添加单元测试。

///

### 创建数据

现在创建工具函数来创建数据。

它的步骤是：

* 使用您的数据创建一个 SQLAlchemy 模型*实例。*
* 使用`add`来将该实例对象添加到数据库会话。
* 使用`commit`来将更改提交到数据库（以便保存它们）。
* 使用`refresh`来刷新您的实例对象（以便它包含来自数据库的任何新数据，例如生成的 ID）。

```Python hl_lines="18-24  31-36"
{!../../docs_src/sql_databases/sql_app/crud.py!}
```

/// tip

 *       class or its <i>trusted</i> dependencies is badly broken), this is what ordinary Java
 *       assertions are for. Note that assertions are not enabled by default; they are essentially
 *       considered "compiled comments."
 *   <li>An explicit {@code if/throw} (as illustrated below) is always acceptable; we still
 *       recommend using our {@link VerifyException} exception type. Throwing a plain {@link
 *       RuntimeException} is frowned upon.

Como ele roda um comando após o outro, modificando e revertendo muitos arquivos, ele demora um pouco para concluir, então pode ser um pouco mais fácil utilizar `scripts/format.sh` frequentemente e `scripts/format-imports.sh` somente após "commitar uma branch".

## Documentação

Primeiro, tenha certeza de configurar seu ambiente como descrito acima, isso irá instalar todas as requisições.

///

## `Annotated`인 의존성 공유하기

위의 예제에서 몇몇 작은 **코드 중복**이 있다는 것을 보았을 겁니다.

`common_parameters()`의존을 사용해야 한다면, 타입 명시와 `Depends()`와 함께 전체 매개변수를 적어야 합니다:

```Python
commons: Annotated[dict, Depends(common_parameters)]
```

하지만 `Annotated`를 사용하고 있기에, `Annotated` 값을 변수에 저장하고 여러 장소에서 사용할 수 있습니다:

//// tab | Python 3.10+

```Python hl_lines="12  16  21"

	lineNum       int   // Line number in source file.
	errorLine     int   // Line number of last error.
	errorCount    int   // Number of errors.
	sawCode       bool  // saw code in this file (as opposed to comments and blank lines)
	pc            int64 // virtual PC; count of Progs; doesn't advance for GLOBL or DATA.
	input         []lex.Token
	inputPos      int
	pendingLabels []string // Labels to attach to next instruction.

		return
	}

	// Check if config param requested is valid.
	defKVS, ok := DefaultKVS[subSys]
	if !ok {
		return
	}

	defValue, isFound := defKVS.Lookup(cfgParam)
	// Comments usually are absent from `defKVS`, so we handle it specially.
	if !isFound && cfgParam == Comment {
		defValue, isFound = "", true
	}
	if !isFound {
		return
	}

	if target == "" {

        addr = getCachedAddress(name);

        if ( addr == null ) {
            /*
             * This is almost exactly like InetAddress.java. See the
             * comments there for a description of how the LOOKUP_TABLE prevents
             * redundant queries from going out on the wire.
             */
            if ( ( addr = (NbtAddress) checkLookupTable(name) ) == null ) {

      pos = indexIn(string, oldpos);
    } while (pos != -1);

    buf.append(string, oldpos, len);
    return buf.toString();
  }

  /**
   * Returns a substring of the input character sequence that omits all matching BMP characters from
   * the beginning and from the end of the string. For example:
   *
   * <pre>{@code
   * CharMatcher.anyOf("ab").trimFrom("abacatbab")
   * }</pre>
   *

  public NullPointerTester() {
    try {
      /*
       * Converter.apply has a non-nullable parameter type but doesn't throw for null arguments. For
       * more information, see the comments in that class.
       *
       * We already know that that's how it behaves, and subclasses of Converter can't change that
       * behavior. So there's no sense in making all subclass authors exclude the method from any

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;

import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.core.misc.Pair;
import org.codelibs.core.net.UuidUtil;