标签: mysql-python

我使用以下查询:

select count(*) from Table1 where CurrentDateTime>'2012-05-28 15:34:02.403504' and Error not in ('Timeout','Connection Error');

令人惊讶的是,此语句不包含具有错误值为NULL的行.我的意图是仅将具有错误值的行过滤为"超时"(或)"连接错误".我需要提供一个附加条件(OR错误为NULL)来检索正确的结果.

为什么MYSQL使用NULL值过滤掉结果？我认为IN关键字将返回一个布尔结果(1/0),现在我明白一些MYSQL关键字不返回布尔值,它也可能返回NULL ....但为什么它将NULL视为特殊？

我在Mac OSX Mountain Lion上构建MySQLdb时遇到了麻烦.从OSX Lion升级到OSX Mountain Lion后,我也下载并安装了Xcode 4.4.然后,我转到Xcode的Preference> Downloads并安装了命令行工具.

我已经下载了MySQL-python ver.1.2.3来自http://sourceforge.net/projects/mysql-python/

我跑的时候

python setup.py build

我得到以下消息:

running build
running build_py
copying MySQLdb/release.py -> build/lib.macosx-10.6-intel-2.7/MySQLdb
running build_ext
building '_mysql' extension
gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -g -O2 -DNDEBUG -g -O3 -Dversion_info=(1,2,3,'final',0) -D__version__=1.2.3 -I/usr/local/mysql/include -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c _mysql.c -o build/temp.macosx-10.6-intel-2.7/_mysql.o -Os -g -fno-common -fno-strict-aliasing -arch x86_64
unable to execute gcc-4.2: No such file or directory
error: command 'gcc-4.2' failed with exit status 1

但是,gcc存在.我跑的时候

gcc

我明白了

i686-apple-darwin11-llvm-gcc-4.2: no input files

下面是我发现的类似问题,但它的解决方案正是我已经做过的,对我来说不起作用.

如何在Mountain Lion上安装MySQLdb

我正在使用所有软件的最新版本(Django,Python,virtualenv,MySQLdb),我无法使用它.当我从virtualenv外部的python提示符中运行"import MySQLdb"时,它可以工作,里面写着"ImportError:没有名为MySQLdb的模块".

我正在努力学习Python和Linux Web开发.我知道使用SQLLite是最简单的,但是我想学习如何开发比我在.NET中可以做的更大规模的应用程序.我已经阅读了Google上的每篇博文和StackOverflow上的每篇帖子,他们都建议我运行"sudo pip install mysql-python",但它只是说"要求已经满足:/ usr/lib/pymodules /中的mysql-python" python2.7"

任何帮助,将不胜感激!我被困在这里并且不想放弃,只是回到微软技术上这样做,因为我甚至无法启动和运行基本开发环境.

我创建一个连接到mysql的python程序.

我需要检查一个表是否包含数字1,以表明它已成功连接,这是我的代码到目前为止:

xcnx.execute('CREATE TABLE settings(status INT(1) NOT NULL)')
  xcnx.execute('INSERT INTO settings(status) VALUES(1)')
  cnx.commit()
  sqlq = "SELECT * FROM settings WHERE status = '1'"
  xcnx.execute(sqlq)
  results = xcnx.fetchall()
  if results =='1':
    print 'yep its connected'
  else:
    print 'nope not connected'

我错过了什么？我是一个sql noob,谢谢你们.

每次我重启MySQL服务器

bitnami@xxx:/$ sudo opt/bitnami/ctlscript.sh start server

WWarning: World-writable config file '/opt/bitnami/mysql/my.cnf' is ignored
Warning: World-writable config file '/opt/bitnami/mysql/my.cnf' is ignored
121120 12:30:18 mysqld_safe Logging to '/opt/bitnami/mysql/data/mysqld.log'.
121120 12:30:18 mysqld_safe Starting mysqld daemon with databases from /opt/bitnami/mysql/data
121120 12:30:20 mysqld_safe mysqld from pid file /opt/bitnami/mysql/data/ip-10-136-14-170.pid ended
/opt/bitnami/mysql/scripts/ctl.sh : mysql  could not be started

服务器响应以下错误:

(2002,"无法通过socket连接到本地MySQL服务器'/tmp/mysql.sock'(2)")

请告诉我我必须做些什么来解决这个问题.

这个错误破坏了我在Mac 10.7.5上的python-mysql安装.这是步骤

1. 安装的python是2.7.1,mysql是5.6位的64位.
2. 正在安装的python-mysql是1.2.4,也尝试过1.2.3

3. 安装配置

   1) sudo ln -s /usr/local/mysql/lib /usr/local/mysql/lib/mysql
   2) Edit the setup_posix.py and change the following mysql_config.path = "mysql_config" to mysql_config.path = "/usr/local/mysql/bin/mysql_config" 
   3) sudo python setup.py build
   

   Run Code Online (Sandbox Code Playgroud)

这是构建的堆栈跟踪

running build
running build_py
copying MySQLdb/release.py -> build/lib.macosx-10.7-intel-2.7/MySQLdb
running build_ext
building '_mysql' extension
llvm-gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -g -Os -pipe -fno-common -fno-strict-aliasing -fwrapv -mno-fused-madd -DENABLE_DTRACE -DMACOSX -DNDEBUG -Wall -Wstrict-prototypes -Wshorten-64-to-32 -DNDEBUG -g -fwrapv -Os -Wall -Wstrict-prototypes -DENABLE_DTRACE -pipe -Dversion_info=(1,2,4,'final',1) -D__version__=1.2.4 -I/usr/local/mysql/include -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c _mysql.c -o build/temp.macosx-10.7-intel-2.7/_mysql.o -Wno-null-conversion -Os …

我有一个Python程序,它在后台运行数周,并且每隔一段时间就进行一次数据库查询.为此,我使用ORM peewee(版本2.2.1).我MySQL用作后端.

最近我遇到了访问数据库的反复出现的问题,通常是在运行程序几天之后.引起的错误peewee是

peewee.OperationalError: (2006, 'MySQL server has gone away')

追溯是深入的peewee.我在这里发布,但由于我的virtualenv文件名太长,我缩短它们:

  File ".../local/lib/python2.7/site-packages/peewee.py", line 2910, in save
    ret_pk = self.insert(**field_dict).execute()
  File ".../local/lib/python2.7/site-packages/peewee.py", line 2068, in execute
    return self.database.last_insert_id(self._execute(), self.model_class)
  File ".../local/lib/python2.7/site-packages/peewee.py", line 1698, in _execute
    return self.database.execute_sql(sql, params, self.require_commit)
  File ".../local/lib/python2.7/site-packages/peewee.py", line 2232, in execute_sql
    self.commit()
  File ".../local/lib/python2.7/site-packages/peewee.py", line 2104, in __exit__
    reraise(new_type, new_type(*exc_value.args), traceback)
  File ".../local/lib/python2.7/site-packages/peewee.py", line 2223, in execute_sql
    res = cursor.execute(sql, params or ())
  File ".../local/lib/python2.7/site-packages/MySQLdb/cursors.py", line 205, …

我想得到一个表的列名,但其中有数百万个数据.所以我不能用:

cursor.execute("SELECT * FROM table_name")
print cursor.description

在sqlite3中,我这样做

crs.execute("PRAGMA table_info(%s)" %(tablename[0]))
for info in crs:
    print info

但这不适用于python mysqldb.谁知道怎么做？

在with语句中创建的变量的范围在with块之外(请参阅:使用with-statement在with-block之外可用的变量定义？).但是当我运行以下代码时:

class Foo:
    def __init__(self):
        print "__int__() called."

    def __del__(self):
        print "__del__() called."

    def __enter__(self):
        print "__enter__() called."
        return "returned_test_str"

    def __exit__(self, exc, value, tb):
        print "__exit__() called."

    def close(self):
        print "close() called."

    def test(self):
        print "test() called."

if __name__ == "__main__":
    with Foo() as foo:
        print "with block begin???"
        print "with block end???"

    print "foo:", foo  # line 1

    print "-------- Testing MySQLdb -----------------------"
    with MySQLdb.Connect(host="xxxx", port=0, user="xxx", passwd="xxx", db="test") as my_curs2:
        print …

我是python的新手，我正在尝试涉及一些MySql的django框架，并在尝试执行pip install mysqlclientcmd消息时遇到了此错误。

   Failed building wheel for mysqlclient
  Running setup.py clean for mysqlclient
Failed to build mysqlclient
Installing collected packages: mysqlclient
  Running setup.py install for mysqlclient ... error
    Complete output from command c:\users\ronanl~1\envs\py1\scripts\python.exe -u -c "import setuptools, tokenize;__file__='C:\\Users\\RONANL~1\\AppData\\Local\\Temp\\pip-install-pkbqy3t3\\mysqlclient\\setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record C:\Users\RONANL~1\AppData\Local\Temp\pip-record-moxwf7lu\install-record.txt --single-version-externally-managed --compile --install-headers c:\users\ronanl~1\envs\py1\include\site\python3.7\mysqlclient:
    running install
    running build
    running build_py
    creating build
    creating build\lib.win32-3.7
    copying _mysql_exceptions.py -> build\lib.win32-3.7
    creating build\lib.win32-3.7\MySQLdb
    copying MySQLdb\__init__.py -> build\lib.win32-3.7\MySQLdb
    copying MySQLdb\compat.py -> build\lib.win32-3.7\MySQLdb
    copying MySQLdb\connections.py -> build\lib.win32-3.7\MySQLdb …