database-connection

问题 I'm running a django-celery application on Ubuntu-12.04. When I run a celery task from my web interface, I get the following error, taken form postgresql-9.3 logfile (maximum level of log): 2013-11-12 13:57:01 GMT tss_usr 8113 LOG: could not receive data from client: Connection reset by peer tss_usr is the postgresql user of the django application database and (in this example) 8113 is the pid of the process who killed the connection, I guess. Have you got any idea on why this happens or at

问题 I'm running a django-celery application on Ubuntu-12.04. When I run a celery task from my web interface, I get the following error, taken form postgresql-9.3 logfile (maximum level of log): 2013-11-12 13:57:01 GMT tss_usr 8113 LOG: could not receive data from client: Connection reset by peer tss_usr is the postgresql user of the django application database and (in this example) 8113 is the pid of the process who killed the connection, I guess. Have you got any idea on why this happens or at

问题 My DBA says that there are way too many connection open and he thinks it is my code in .net that is leaving them open. I am using LINQ querys and EF code first. Example Method: public List<Stuff> GetStuff() { var db = new DBContext(); var results = db.stuff.toList(); return results; } Do I need to dispose the db var once I am done? My understanding is that I didn't need to in EF and LINQ. Please point me to a Microsoft documentation about managing connection in code or best practices for LINQ

问题 I am trying to send INSERT statements to mysql from Python using pymysql. Based on some conditions if I find a particular file, I insert it's contents to it's corresponding table in database. Currently I have two tables CACCT and PAUTH. I have separate functions for table specific INSERTs. The functions are: 1. load_json_sql_CACCT() 2. load_json_sql_PAUTH() My main function is recon(). mysql_conn_dev = mysql.connect(host="xxxx", user="xxx", db="xxx") cur = mysql_conn_dev.cursor(mysql.cursors

问题 From the c3p0 documentation: For some applications, high performance is more important than the risk of an occasional database exception. In its default configuration, c3p0 does no Connection testing at all. Setting a fairly long idleConnectionTestPeriod , and not testing on checkout and check-in at all is an excellent, high-performance approach. If I understand the meaning of the c3p0 configuration properties correctly, if the database becomes unavailable for a short period of time and then

问题 I am actually reading Oracle-cx_Oracle tutorial. There I came across non-pooled connections and DRCP, Basically I am not a DBA so I searched with google but couldn't found any thing. So could somebody help me understand what are they and how they are different to each other. Thank you. 回答1: Web tier and mid-tier applications typically have many threads of execution, which take turns using RDBMS resources. Currently, multi-threaded applications can share connections to the database efficiently

问题 I would like to execute FireDAC connection editor at run time, but haven't found which class is the Component Editor for TFDConnection . For example, it is easy to find out which class is the Component Editor for TADOConnection. 回答1: You can excute FireDac connection editor by calling Execute method of TfrmFDGUIxFormsConnEdit which you can find it in FireDAC.VCLUI.ConnEdit unit. Here is an example how to do it: Uses ... FireDAC.VCLUI.ConnEdit; .. var FDConnEditor : TfrmFDGUIxFormsConnEdit;

问题 I would like to execute FireDAC connection editor at run time, but haven't found which class is the Component Editor for TFDConnection . For example, it is easy to find out which class is the Component Editor for TADOConnection. 回答1: You can excute FireDac connection editor by calling Execute method of TfrmFDGUIxFormsConnEdit which you can find it in FireDAC.VCLUI.ConnEdit unit. Here is an example how to do it: Uses ... FireDAC.VCLUI.ConnEdit; .. var FDConnEditor : TfrmFDGUIxFormsConnEdit;

问题 Excepcion:com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure ... Caused by: java.net.SocketException: Broken pipe I have already read a lot of question similar to this one. So, before declaring this question 'unworthy' let me clarify some things My JDBC link is fully working. No problem of authentication Sql is up and running The max_connections , wich is 300, is never reached The concurrent thread connections are always between 5 and 9 Im using MySQL 5.0.95

问题 So we have SQL Server 2008 R2 Express running on a local server, and a bunch of machines on the same LAN use a program I wrote in C# to access said server. All the machines in the building except one can connect quite happily. Connection string is: Data Source=[IP address here],53535\SQLEXPRESS;Initial Catalog=EMS_Main;;User ID=EMSUser;Password=[password here]; Exact error message is: "A network-related or instance-specific error occurred while establishing a connection to SQL Server. The