Net Programmers Learn Oracle Series (22): Analytical Functions (OVER)

1,Function grammar 1.1,Syntax overview 1.2,Window detail 1.2.1,ROWS window 1.2.2,RANGE window 2,Function usage 2.1,General Statistical Class Function 2.2,Data Sorting Class Function 2.3,Data Distribution Class Function 2.4,Statistical analysis class function 3,Supplementary case 4,summary Analytical functions are used to cal ...

Posted by xSN1PERxEL1TEx on Sat, 20 Apr 2019 10:12:35 -0700

Python operates MySQL database

Introduction: Python standard database interface is Python DB-API. Python DB-API provides database application programming interface for developers. Can access Python database interface and API View a detailed list of supported databases. For different databases, you need to download different DB API modules. For example, you need to access ...

Posted by OriginalSunny on Sat, 20 Apr 2019 03:27:33 -0700

Oracle Diagnostic Case - One of Sql_trace

Problem Description: This is a diagnostic case to help a company. Application is a background news release system. Symptoms are that access to news pages via links is extremely slow It usually takes ten seconds to return. This performance is intolerable to users. Operating System: SunOS 5.8 Database Version: 8.1.7   1. Check and track dat ...

Posted by incarnate on Sat, 20 Apr 2019 00:09:35 -0700

Database Operating Tool-Query Runner

After learning about JDBC and database operations, it is obvious that writing JDBC code is not an easy task. In order to help us learn more efficiently and get rid of the heavy code of JDBC, Tong gave us a detailed introduction to a component that simplifies JDBC operations, DBUtils. Today we have mainly studied the two classes and an inter ...

Posted by shwanky on Fri, 19 Apr 2019 23:15:33 -0700

Reprint: A very useful summary of PHP common functions

1. PHP Encryption and Decryption PHP encryption and decryption function can be used to encrypt some useful strings stored in the database, and through reversible decryption of strings, the function uses base64 and MD5 encryption and decryption. function encryptDecrypt($key, $string, $decrypt){ if($decrypt){ $decrypted = rtrim(mcry ...

Posted by captainplanet17 on Fri, 19 Apr 2019 22:18:33 -0700

Tencent cloud database team: the use of sql-parser component in phpMyAdmin

phpMyAdmin is an open source database management tool based on Web-side operation, supporting the management of MySQL and MariDB databases. phpMyAdmin's program is mainly developed with php and javascript. Its installation and use are relatively simple and many related introductions are not repeated. Today we will introduce a core component of ...

Posted by jboku on Fri, 19 Apr 2019 18:09:34 -0700

Detailed description of JDBC connection database

I. concept 1. In order to enable the program to operate the database and the tables in the database, each database will provide a set of drivers to connect and operate the database, and the drivers of each database are different. For example, MySQL database is driven by mysql, Oracle database is driven by oracle, so if the program we write wan ...

Posted by jmajeremy on Fri, 19 Apr 2019 17:36:34 -0700

Net Programmers Learn Oracle Series (21): Grouped Query (GROUP BY)

1,GROUP BY Standard Grouping 1.1,Overview of GROUP BY 1.2,The difference between WHERE and HAVING? 2,GROUP BY Extended Grouping 2.1,ROLLUP grouping 2.2,CUBE grouping 2.3,GROUPING SETS grouping 2.4,Complex grouping (combination column grouping, duplicate column grouping, connection grouping) 3,GROUP BY Extension Function 3.1,GROUPI ...

Posted by andy666 on Fri, 19 Apr 2019 17:06:32 -0700

Custom Exploded Database Framework (5) The Final Practice

Preface After learning and accumulating the basic knowledge, we finally come to the final battle and customize the database framework. The framework is used by referring to some popular database frameworks, such as Litepal. text First, let's sort out the flow chart of our framework. Starting with the initialization of the database, we fi ...

Posted by FredFredrickson2 on Fri, 19 Apr 2019 10:39:33 -0700

Basic usage of Android database

Android database SQliteOpenHelper First, we encapsulate a SQliteOpenHelper, which is Android's database help class. The general work of creating tables and encapsulating methods of adding, deleting, modifying and checking are all put in this class. public class LocalDataHelper extends SQLiteOpenHelper{ public static final String det ...

Posted by jdorma0 on Thu, 18 Apr 2019 19:57:34 -0700