Tag : Sql

If so, don’t say that you don’t open up new sources of income, but only care about whether you charge for commercial projects, thank you very much. For the enterprise edition, you can use the rest at will, but there is ..

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There are some mongodb data that need to be statistically analyzed, and there are correlations among multiple collections.If mapReduce is used, it will be too complicated and the performance will be very poor.What is the usual solution? Have you found a solution to thi..

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Looking at NoSQL these days, I still don’t quite understand the conversion from tables, rows and columns in traditional relational databases to NoSQL. For example, the simplest blog database design has a classification table, an article table and n articles for each classification. How does this traditional relational database design change to Mongodb and Redis? ..

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[root@host up]# ./main [ORM]2018/10/02 01:48:15 register db Ping `default`, Binary was compiled with ‘CGO_ENABLED=0’, go-sqlite3 requires cgo to work. This is a stub must have one register DataBase alias named `default` [root@host up]# The web application written by beego is cross-compiled into Linux version under Mac OS and cannot be executed. After opening CGO, it ..

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Like SQLServerProfiler, any session that executes a certain SQL can be recorded and displayed? For versions after 10g, dbms_monitor package commands can be used to start database and session-level tracking. For previous versions, 10046 events can only be used. dbms_monitor.session_trace_enable(sid => 127, serial => 29) dbms_monitor.session_trace_disable(sid => 127, serial => 29) After trace is finished, ..

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1. It is said that load balancing is required, but at the beginning, one server must establish a connection with the client and inform the client which load server to establish a connection with, or transfer the client’s request to the load server. How are the initial large data volume connection requests and data transfers ..

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I now have a function to write data, but I need to look up the data from another table before writing. Then I will use it twice in a function insideconnection.query(sql,function(){….})However, if the. query () function does not seem to be blocked, the second. query () function will be executed before the first. query () ..

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First, nodejs wrote a small crawler, climbed down a little bit of data, and then wanted to write it into the database.Nodejs code: Sql = “insert into “plus table plus” values (“plus maxCol plus”, “plus data[i].url plus”‘,’ “plus data[i].name plus”‘); connection.query(sql, function(err, results, fields){ ! err ? console.log(“success! ! !” ) : console.log(err); }); After ..

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For example, if you want to write formatted sql, you must have multiple lines. For multi-line strings, what is the shortcut or tool to write with nodejs? It is too much trouble to write the plus signs one by one. The editor used is vim, and it is better to have relevant shortcut recommendations. There ..

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