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This article mainly explains how to use SmartDb in C++. Interested friends may wish to take a look. The method introduced in this paper is simple, fast and practical. Let's let Xiaobian take you to learn "how to use SmartDb in C++"!

Sqlite is a very lightweight open source database, used in embedded systems more often, storage management data is very convenient, Sqlite library based on C language API, use up is also quite simple, but there is a little bad API use up a little cumbersome, in addition to different occasions, code reuse rate is very low, have to rewrite the code, increase the workload, code to reuse as much as possible, only valuable. SmartDB encapsulates sqlite in a layer (template metaprogramming based on C++11), shielding us from many details, making it easy to use. Performance and flexibility are balanced with ease of use.

Using SmartDb to manipulate the database is much easier:

Take a look at the sample code:

void TestPerformance(){ SmartDB db; db.Open("test.db"); //Open database const string sqlcreat = "CREATE TABLE if not exists TestInfoTable(ID INTEGER NOT NULL, KPIID INTEGER, CODE INTEGER, V1 INTEGER, V2 INTEGER, V3 REAL, V4 TEXT);"; if (! db. Execute (sqlcreate)) //Execute sql statements return;

const string sqlinsert = "INSERT INTO TestInfoTable(ID, KPIID, CODE, V1, V2, V3, V4) VALUES(?, ?, ?, ?, ?, ?, ?); "; bool ret = db.Prepare(sqlinsert); db.Begin(); for (size_t i = 0; i

< 10; i++) //00000 { ret = db.ExcecuteArgs(i, i, i, i, i, i + 1.25, "it is a test"); if (!ret) break; } if (ret) db.Commit(); //提交事务 else db.RollBack(); //回滚 auto p = db.Query("select * from TestInfoTable"); rapidjson::StringBuffer buffer; rapidjson::PrettyWriter pretty_writer(buffer); //PrettyWriter是格式化的json，如果是Writer则是换行空格压缩后的json p->

Accept(pretty_writer); //Print to screen cout

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