How to Find the Most Recent Date Across Multiple Date Columns in SQL?
SQL multi-column date maximum value acquisition skills
When working with tables containing multiple date or timestamp columns, you need to identify the latest value for each row. This article provides a SQL solution for getting the maximum value in multiple columns, converting raw data into a more manageable format.
Problem Description
Suppose there is a table called "TableName" with the following columns: [Number], [Date1], [Date2], [Date3], and [Cost]. The goal is to convert this table into a new table that displays the following information for each row: [Number], [Most_Recent_Date], and [Cost].
Solution
In SQL Server, an effective way to get the maximum value of multiple columns is to use T-SQL and SQL Server syntax:
SELECT [Other Fields], (SELECT Max(v) FROM (VALUES (date1), (date2), (date3),...) AS value(v)) as [MaxDate] FROM [YourTableName]
This code uses the table value constructor "VALUES" to build a temporary table that contains the values of the individual columns in the original table. The SELECT statement in parentheses calculates the maximum value of each row and assigns it to the alias "[MaxDate]". By combining this information with other fields from the original table, we get a new table with the desired output format.
The above is the detailed content of How to Find the Most Recent Date Across Multiple Date Columns in SQL?. For more information, please follow other related articles on the PHP Chinese website!

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

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics



The article discusses using MySQL's ALTER TABLE statement to modify tables, including adding/dropping columns, renaming tables/columns, and changing column data types.

Article discusses configuring SSL/TLS encryption for MySQL, including certificate generation and verification. Main issue is using self-signed certificates' security implications.[Character count: 159]

Article discusses strategies for handling large datasets in MySQL, including partitioning, sharding, indexing, and query optimization.

Article discusses popular MySQL GUI tools like MySQL Workbench and phpMyAdmin, comparing their features and suitability for beginners and advanced users.[159 characters]

The article discusses dropping tables in MySQL using the DROP TABLE statement, emphasizing precautions and risks. It highlights that the action is irreversible without backups, detailing recovery methods and potential production environment hazards.

InnoDB's full-text search capabilities are very powerful, which can significantly improve database query efficiency and ability to process large amounts of text data. 1) InnoDB implements full-text search through inverted indexing, supporting basic and advanced search queries. 2) Use MATCH and AGAINST keywords to search, support Boolean mode and phrase search. 3) Optimization methods include using word segmentation technology, periodic rebuilding of indexes and adjusting cache size to improve performance and accuracy.

Article discusses using foreign keys to represent relationships in databases, focusing on best practices, data integrity, and common pitfalls to avoid.

The article discusses creating indexes on JSON columns in various databases like PostgreSQL, MySQL, and MongoDB to enhance query performance. It explains the syntax and benefits of indexing specific JSON paths, and lists supported database systems.
