You also get error checks for incorrect type operations:

<img src="/img/tutorial/body/image04.png">

This is not by chance, the whole framework was built around that design.

And it was thoroughly tested at the design phase, before any implementation, to ensure it would work with all the editors.

There were even some changes to Pydantic itself to support this.

These last **three consecutive releases** are independent so that you can **migrate gradually**:

* First to FastAPI `0.68.2`, with no breaking changes, but upgrading all the sub-dependencies.
* Next to FastAPI `0.69.0`, which upgrades Starlette to `0.15.0`, with AnyIO support, and a higher chance of having breaking changes in your code.

	})
	assertEqualSQL(t, `SELECT * FROM "users" WHERE id = 100 AND "users"."deleted_at" IS NULL ORDER BY age desc LIMIT 10`, sql)

	// after model changed
	if DB.Statement.DryRun || DB.DryRun {
		t.Fatal("Failed expect DB.DryRun and DB.Statement.ToSQL to be false")
	}

	if DB.Statement.SQL.String() != "" {
		t.Fatal("Failed expect DB.Statement.SQL to be empty")

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            return dstIndex - start;
        }

        /* The message provided to batch has a batchLimit that is
         * higher than the current batchLevel so we will now encode
         * that chained message. Before doing so we must increment
         * the batchLevel of the andx message in case it itself is an
         * andx message and needs to perform the same check as above.
         */

///

## Reduce duplication { #reduce-duplication }

Reducing code duplication is one of the core ideas in **FastAPI**.

As code duplication increments the chances of bugs, security issues, code desynchronization issues (when you update in one place but not in the others), etc.

And these models are all sharing a lot of the data and duplicating attribute names and types.

        }
        return instance;
      }
    }
    throw new IllegalArgumentException(
        "No appropriate constructor for exception of type "
            + exceptionClass
            + " in response to chained exception",
        cause);
  }

  private static <X extends Exception> List<Constructor<X>> preferringStringsThenThrowables(
      List<Constructor<X>> constructors) {

implementation. This simple-looking method is where all the HTTP work happens, producing a response to satisfy the request. If `chain.proceed(request)` is being called more than once previous response bodies must be closed.

Interceptors can be chained. Suppose you have both a compressing interceptor and a checksumming interceptor: you'll need to decide whether data is compressed and then checksummed, or checksummed and then compressed. OkHttp uses lists to track interceptors, and interceptors are...

   * each given element has increased by one since the test collection was created, and the number
   * of occurrences of all other elements has not changed.
   *
   * <p>Note: This means that a test like the following will fail if {@code collection} is a {@code
   * Set}:
   *
   * <pre>
   * collection.add(existingElement);

        }
        return instance;
      }
    }
    throw new IllegalArgumentException(
        "No appropriate constructor for exception of type "
            + exceptionClass
            + " in response to chained exception",
        cause);
  }

  private static <X extends Exception> List<Constructor<X>> preferringStringsThenThrowables(
      List<Constructor<X>> constructors) {