是否有一种方法可以在执行查询时显示Django正在运行的SQL ?


当前回答

看一下debug_toolbar,它对调试非常有用。

文档和源代码可以在http://django-debug-toolbar.readthedocs.io/上找到。

其他回答

我相信这应该工作,如果你使用PostgreSQL:

from django.db import connections
from app_name import models
from django.utils import timezone

# Generate a queryset, use your favorite filter, QS objects, and whatnot.
qs=models.ThisDataModel.objects.filter(user='bob',date__lte=timezone.now())

# Get a cursor tied to the default database
cursor=connections['default'].cursor()

# Get the query SQL and parameters to be passed into psycopg2, then pass
# those into mogrify to get the query that would have been sent to the backend
# and print it out. Note F-strings require python 3.6 or later.
print(f'{cursor.mogrify(*qs.query.sql_with_params())}')

看一下debug_toolbar,它对调试非常有用。

文档和源代码可以在http://django-debug-toolbar.readthedocs.io/上找到。

从django获取查询结果到数据库(使用正确的参数替换) 你可以使用这个函数:

from django.db import connection

def print_database_query_formatted(query):
    sql, params = query.sql_with_params()
    cursor = connection.cursor()
    cursor.execute('EXPLAIN ' + sql, params)
    db_query = cursor.db.ops.last_executed_query(cursor, sql, params).replace('EXPLAIN ', '')

    parts = '{}'.format(db_query).split('FROM')
    print(parts[0])
    if len(parts) > 1:
        parts = parts[1].split('WHERE')
        print('FROM{}'.format(parts[0]))
        if len(parts) > 1:
            parts = parts[1].split('ORDER BY')
            print('WHERE{}'.format(parts[0]))
            if len(parts) > 1:
                print('ORDER BY{}'.format(parts[1]))

# USAGE
users = User.objects.filter(email='admin@admin.com').order_by('-id')
print_database_query_formatted(users.query)

输出示例

SELECT "users_user"."password", "users_user"."last_login", "users_user"."is_superuser", "users_user"."deleted", "users_user"."id", "users_user"."phone", "users_user"."username", "users_user"."userlastname", "users_user"."email", "users_user"."is_staff", "users_user"."is_active", "users_user"."date_joined", "users_user"."latitude", "users_user"."longitude", "users_user"."point"::bytea, "users_user"."default_search_radius", "users_user"."notifications", "users_user"."admin_theme", "users_user"."address", "users_user"."is_notify_when_buildings_in_radius", "users_user"."active_campaign_id", "users_user"."is_unsubscribed", "users_user"."sf_contact_id", "users_user"."is_agree_terms_of_service", "users_user"."is_facebook_signup", "users_user"."type_signup" 
FROM "users_user" 
WHERE "users_user"."email" = 'admin@admin.com' 
ORDER BY "users_user"."id" DESC

它基于这个票证评论:https://code.djangoproject.com/ticket/17741#comment:4

虽然可以使用提供的代码来完成,但我发现使用调试工具栏应用程序是显示查询的一个很好的工具。你可以从github下载。

这使您可以选择显示在给定页面上运行的所有查询以及查询所花费的时间。它还汇总了页面上的查询数量以及用于快速查看的总时间。当你想了解Django ORM在幕后做了什么时,这是一个很好的工具。它也有很多其他不错的功能,你可以使用,如果你喜欢。

下面基于https://code.djangoproject.com/ticket/17741:返回有效的SQL查询

def str_query(qs):
    """
    qs.query returns something that isn't valid SQL, this returns the actual
    valid SQL that's executed: https://code.djangoproject.com/ticket/17741
    """
    cursor = connections[qs.db].cursor()
    query, params = qs.query.sql_with_params()
    cursor.execute('EXPLAIN ' + query, params)
    res = str(cursor.db.ops.last_executed_query(cursor, query, params))
    assert res.startswith('EXPLAIN ')
    return res[len('EXPLAIN '):]