Rollback Error

PHP pdo transaction rollback code example $ this-> beginTransaction (); $ this-> exec ('update people set age = 2'); // $ step1 = mysql tutorial _error (); / / your class, Change to the implementation of sql error, get the error code, the corresponding function $ this-> exec ('INSERT INTO course (course, num) ...

Start Hadoop start-all.sh Turn off Hadoop stop-all.sh View the file list to view the files in the/user/admin/aaron directory in HDFs. 　　Hadoop Fs-ls/user/admin/aaron Lists all the files (including the files under subdirectories) in the/user/admin/aaron directory in HDFs. Hadoop fs-lsr/user ...

As an outstanding representative of the Object relational database, Oracle is undoubtedly the most powerful. Whether it's the size of the database, the support of multimedia data types, the parallelism of SQL operations replication, or the security services, Oracle is much stronger than Sybase, Informix, Added to the latest version of the Oracle8.0.4 is to enhance the characteristics of this, but also introduced a number of new features, such as: Data partitioning (partitioning), Object-relational technology (objects relational T ...

1 Hadoop fs ----------------------------------------------- --------------------------------- The hadoop subcommand set executes on the root of the / home directory on the machine Is / user / root --------------------------------------------- ----------...

Overview All Hadoop commands are raised by the Bin/hadoop script. Do not specify parameters running the Hadoop script prints the description of all commands. Usage: Hadoop [--config confdir] [COMMAND] [generic_options] [command_options] Hadoop has an option parsing framework for parsing general options and running classes. Command option description--config confdir overwrite default configuration directory ...

Objective the goal of this document is to provide a learning starting point for users of the Hadoop Distributed File System (HDFS), where HDFS can be used as part of the Hadoop cluster or as a stand-alone distributed file system. Although HDFs is designed to work correctly in many environments, understanding how HDFS works can greatly help improve HDFS performance and error diagnosis on specific clusters. Overview HDFs is one of the most important distributed storage systems used in Hadoop applications. A HDFs cluster owner ...

After the team's CSS3.0 Chinese handbook in the domestic starting, the recent popular everywhere blowing HTML5.0 and CSS3.0 spring Breeze; It seems that in this browser to ridicule each other in the era, the achievements of a lot of industry gossip topic. Years ago, Google's Chrome team came to the company to do the related exchanges, the company asked me to do a preliminary discussion plan. So I thought about it, and it said three points: Chrome for more than 12px font size support Chrome's developer tools are integrated, but less flexible than firebug ...

1. Flying test challenges flying open platform that flying large-scale distributed computing system (short flying). Flying expects to assemble thousands of PCs into a "supercomputer" that can provide common computing, storage, and task scheduling services for a wide range of different open services and cloud applications. It can be seen from the flying characteristics of the platform, versatility and large-scale, so flying faces a series of challenges. Challenge one: The contradiction between the complexity of platform software and the rhythm of Internet release. There are many complex distributed modules in flying. The complexity of the module itself multiplied by the ...

Mysql often encountered during the three failures, in this summary. 1, MySQl service can not start We use mysql process, often encounter MySQl service can not start, specific error message: Starting MySQL ERROR.The server quit without updating PID file (/ [FAILED] l / mysql /) For such error,...

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