Difference: 1. in makes a hash connection between the parent query table and the sub-query table, while or performs a loop on the parent query table and then queries the sub-query table; 2. Data without an index The larger the amount, the execution efficiency of in will not drop much, while the execution efficiency of or will drop significantly.
The operating environment of this tutorial: Windows 10 system, Oracle 11g version, Dell G3 computer.
What is the difference between in and or in oracle
a in (1,2,3)(a = 1 or a = 2 or a = 3)
a = 1 && b = 2 or a = 3 is equivalent to the union of the conditions of (a = 1 && b =2) and a = 3
or, or if one of the two conditions is met
in is used to include, for example, select * from table in (a statement or several values)
or: satisfy at most two conditions in: satisfy more conditions
The operations are different
1. in: in is a hash connection between the parent query table and the child query table.
2. or: or performs a loop on the parent query table, and queries the child query table each time the loop loops.
Suitable for different
1. in: in is suitable for situations where the child query table has more data than the parent query table.
2. or: or is suitable for situations where the child query table has less data than the parent query table.
Different execution efficiency
1. In: In the absence of an index, as the amount of data behind in increases, the execution efficiency of in will decrease. There will be too big a drop.
2. or: In the absence of an index, as the amount of data behind or increases, the execution efficiency of or will decrease significantly.
Recommended tutorial: "Oracle Video Tutorial"
The above is the detailed content of What is the difference between in and or in oracle?. For more information, please follow other related articles on the PHP Chinese website!
What Does Oracle Offer? Products and Services ExplainedApr 16, 2025 am 12:03 AMOracleoffersacomprehensivesuiteofproductsandservicesincludingdatabasemanagement,cloudcomputing,enterprisesoftware,andhardwaresolutions.1)OracleDatabasesupportsvariousdatamodelswithefficientmanagementfeatures.2)OracleCloudInfrastructure(OCI)providesro
Oracle Software: From Databases to the CloudApr 15, 2025 am 12:09 AMThe development history of Oracle software from database to cloud computing includes: 1. Originated in 1977, it initially focused on relational database management system (RDBMS), and quickly became the first choice for enterprise-level applications; 2. Expand to middleware, development tools and ERP systems to form a complete set of enterprise solutions; 3. Oracle database supports SQL, providing high performance and scalability, suitable for small to large enterprise systems; 4. The rise of cloud computing services further expands Oracle's product line to meet all aspects of enterprise IT needs.
MySQL vs. Oracle: The Pros and ConsApr 14, 2025 am 12:01 AMMySQL and Oracle selection should be based on cost, performance, complexity and functional requirements: 1. MySQL is suitable for projects with limited budgets, is simple to install, and is suitable for small to medium-sized applications. 2. Oracle is suitable for large enterprises and performs excellently in handling large-scale data and high concurrent requests, but is costly and complex in configuration.
Oracle's Purpose: Business Solutions and Data ManagementApr 13, 2025 am 12:02 AMOracle helps businesses achieve digital transformation and data management through its products and services. 1) Oracle provides a comprehensive product portfolio, including database management systems, ERP and CRM systems, helping enterprises automate and optimize business processes. 2) Oracle's ERP systems such as E-BusinessSuite and FusionApplications realize end-to-end business process automation, improve efficiency and reduce costs, but have high implementation and maintenance costs. 3) OracleDatabase provides high concurrency and high availability data processing, but has high licensing costs. 4) Performance optimization and best practices include the rational use of indexing and partitioning technology, regular database maintenance and compliance with coding specifications.
How to delete oracle library failureApr 12, 2025 am 06:21 AMSteps to delete the failed database after Oracle failed to build a library: Use sys username to connect to the target instance. Use DROP DATABASE to delete the database. Query v$database to confirm that the database has been deleted.
How to create cursors in oracle loopApr 12, 2025 am 06:18 AMIn Oracle, the FOR LOOP loop can create cursors dynamically. The steps are: 1. Define the cursor type; 2. Create the loop; 3. Create the cursor dynamically; 4. Execute the cursor; 5. Close the cursor. Example: A cursor can be created cycle-by-circuit to display the names and salaries of the top 10 employees.
How to export oracle viewApr 12, 2025 am 06:15 AMOracle views can be exported through the EXP utility: Log in to the Oracle database. Start the EXP utility, specifying the view name and export directory. Enter export parameters, including target mode, file format, and tablespace. Start exporting. Verify the export using the impdp utility.
How to stop oracle databaseApr 12, 2025 am 06:12 AMTo stop an Oracle database, perform the following steps: 1. Connect to the database; 2. Shutdown immediately; 3. Shutdown abort completely.
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft
DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software
SublimeText3 Linux new version
SublimeText3 Linux latest version
Dreamweaver CS6
Visual web development tools
MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.
