learn cassandra database

look at the code and other things actually too tired, so I went to learn MongoDB, and then the company MongoDB operation of the live, is in the breadth of an expansion, in the event of the day MySQL is not6, in short, for the DB small white, the most important point is thatthe process of learning cannot be broken。PS above method comparison wild path, suitable for no basic children's shoes, if it is a DBA, such as from Oracle to MySQL, then it is reco

;Importorg.junit.Test; Public classDemo1 {/*** ClassNotFoundException: * > No driver package * > * * SQLException: * > Check 3 parameters: URL, username , password is correct * > check if MySQL server is turned on! */@Test Public voidFUN1 ()throwsClassNotFoundException, SQLException {/** JDBC Four configuration parameters: * > DriverClassName:com.mysql.jdbc.Driver * > Url:jdbc:mysql://localhost: 3306/MYDB3 * > Username:root * > Password:123*/ /** All Java.sql.Driver implementations ar

PrivateDatabasepool () { - Ds.setpassword (Xmldateparse.getpassword ()); - Ds.seturl (Xmldateparse.geturl ()); the Ds.setusername (Xmldateparse.getusername ()); - Ds.setdriverclassname (Xmldateparse.getdriver ()); - - //set the Max data connection pool connection active Count +Ds.setmaxactive (10); - //set the initial connection size +Ds.setinitialsize (2); A //set the min idle size atDs.setminidle (2); - //set the max wait mins -Ds.setmaxwait (2000)

configuration and is more popular. The configuration for permissionentity is as follows: ? This will be configured to set the name of the table, the maximum length of the field, whether it is nullable, and so on, as the data table is generated. third, build the database Write the configuration for each entity, run the project, and the database will be created automatically. By default, EF keeps track of

Tags: log change tle query services DDB style operation based on conditionsSeries Catalogue Learn more about the. Net Core WEB API Development Series Catalog The source code involved in this series: Https://github.com/seabluescn/Blog_WebApi I. Overview This article describes some common database operations, including: Conditional query, sorting, paging, transactions and other basic

(System.Data.Common.DbDataReader reader = cmd.) ExecuteReader ()) {while (reader. Read ()) {Console.WriteLine (reader[0]. ToString () + ";");}}} } console.readkey (); }}}The results are as follows:whichSetautocommit's instructions are as followsCci_default_autocommitCci_default_autocommit is a parameter used to configure whether to make application implemented in CCI interface or CCI-BA Sed interface such as PHP, ODBC, OLE DB, Perl, Python, and Ruby commit automatically. The default value

#coding =utf-8import cx_oracle #引用模块cx_Oracleimport osos.environ[' nls_lang '] = ' simplified Chinese_china. UTF8 ' #编码问题conn =cx_oracle.connect (' xho ', ' sys ', ' LOCALHOST:1521/ORCL ') #连接数据库c =conn.cursor () #获取cursor游标x =c.execute (' select * from weight ') #使用cursor进行各种操作a =x.fetchone () #查询时获取结果集的第一行数据, returns a tuple of print Ab=x.fetchall () #所有行, a row forms a t