Category:DBT

  • SQL Server English date to general date format

    Time:2020-10-30

    Question: The English date format is converted to the general date format. In the Chinese environment, if the conversion script is executed directly, an error will be reportedMessage 241, level 16, status 1, line 1Conversion failed when converting date and / or time from string. Root cause: The English date format does not count as […]

  • Image rental system of Oracle small training

    Time:2020-10-30

    Image rental system: In the United States, due to the good protection of intellectual property rights, there is generally no piracy problem. In addition to watching movies in the cinema, Americans rent CDs in video shops and go home to see them. In this case, there are more shops for shadow rental. In the context […]

  • MySQL installation tutorial

    Time:2020-10-30

    This version of MSI is easy to download and configure automatically 1. Download from official website Address: https://dev.mysql.com/downloads/mysql/   Note: Area 1 is the download location of MSI version, go to download, area 2 is the download location of zip file, which is not recommended, and area 3 is the historical version   Note that […]

  • Processing method of Oracle date type field

    Time:2020-10-30

    (1) In the English version of Oracle, the default date format is’ dd-mon-yy ‘, for example,’ 01-jan-98 ‘ In the Chinese version, the default date format of Oracle is’ Day Month Year ‘, such as’ 21-august-2003′ or ’21-august-03′ (2) Convert string to date Using Oracle inner function to_ date() To_ The parameter of the date() […]

  • Mysql8.0.11 winx64 installation and configuration tutorial

    Time:2020-10-30

    MySQL 8.0.11 winx64 installation tutorial records are as follows, to share with you 1. Import the database installation package, create a new folder (MySQL), and unzip the installation package into the MySQL folder 2. Configure environment variablesLike JDK, go in, select the path editor, add the MySQL directory (note that there is an English semicolon), […]

  • SQL Server common data types

    Time:2020-10-30

    In SQL server, every variable, parameter, expression, etc. has a data type. The data types provided by the system can be divided into several categories, as shown in Table 4-2. Among them, bigint, SQL_ Variant and table are three new data types in SQL Server 2000. The following classification describes the various data types. 1、 […]

  • Collection of reasons for slow query speed of SQL server and optimization suggestions

    Time:2020-10-29

    Collection of reasons for slow query speed of SQL Server There is no index or index is not used (this is the most common problem of slow query, which is a programming defect). The I / O throughput is small, forming a bottleneck effect. The computed column was not created, which caused the query not […]

  • Solution to drive download failure when pychar connects to MySQL

    Time:2020-10-29

    1、 Problem description When the database in pychar is used to connect to MySQL for the first time, the download drive shows that the connection timed out and the download failed  2、 Solutions 1. Download drive from Tsinghua mirror network https://mirrors.tuna.tsinghua.edu.cn/mysql/downloads/Connector-J/ Select the corresponding version, and select the following according to my MySQL version 2. […]

  • Summary of knowledge points of daily maintenance of Oracle Database

    Time:2020-10-29

    First of all, the system tables provided by different versions of the database will be different. You can view the tables provided by the database of this version according to the data dictionary like this: select * from dict where table_name like ‘%SESSION% ‘; You can find some tables, and then according to these tables, […]

  • The method of SQL server backup database stored procedure

    Time:2020-10-29

    SQL Server batch export stored procedures In the query analyzer, select database, right-click task, and select generate script from the pop-up menu ——》”Next step” — “select the database where you want to store the procedure” “Next step” — check “stored procedure” and “next step” Check the name of the stored procedure you want to generate, […]

  • T_ SQL programming

    Time:2020-10-28

    Transact SQL language is a programming language provided by SQL server for users. It is the implementation and extension of standard SQL. It has the main characteristics of standard SQL, At the same time, language elements such as variables, operators, functions and process control are added to make it more powerful.   1. Batch processing, […]

  • DML statement (add, delete, modify) and change table of Oracle Foundation (5)

    Time:2020-10-28

    1、 DML statement (data operation statement) 1. Add data to the table Insert into table name (field name) values (value) Note: 1) only one piece of data can be inserted using the values keyword 2) Pay attention to integrity constraints 3) The inserted values must be in the same order as the fields 4) You […]