SQL Server's medium -efficient rotation conversionQuestion
It may be a performance challenge in SQL Server, especially when dealing with large datasets. This article discusses various methods for optimizing row conversion conversion.
Pivot function
Pivot function is a common choice for this task. Although it is not always the fastest way, it provides a direct and flexible way of conversion:
The polymer function and case expression
SELECT FirstName, Amount, PostalCode, LastName, AccountNumber FROM ( SELECT value, columnName FROM yourTable ) d PIVOT ( MAX(value) FOR columnName IN (FirstName, Amount, PostalCode, LastName, AccountNumber) ) piv;Pivot's replacement method is to use the polymer function and case expression:Multiple connections
In the case of PIVOT or polymerization function, multiple connections can be used:
SELECT MAX(CASE WHEN columnName = 'FirstName' THEN value END) Firstname, MAX(CASE WHEN columnName = 'Amount' THEN value END) Amount, MAX(CASE WHEN columnName = 'PostalCode' THEN value END) PostalCode, MAX(CASE WHEN columnName = 'LastName' THEN value END) LastName, MAX(CASE WHEN columnName = 'AccountNumber' THEN value END) AccountNumber FROM yourTable;dynamic pivot
For the unknown case that needs to be converted, you can use a dynamic SQL to build a PIVOT statement:
SELECT fn.value AS FirstName, a.value AS Amount, pc.value AS PostalCode, ln.value AS LastName, an.value AS AccountNumber FROM yourTable fn LEFT JOIN yourTable a ON fn.someCol = a.someCol AND a.columnName = 'Amount' LEFT JOIN yourTable pc ON fn.someCol = pc.someCol AND pc.columnName = 'PostalCode' LEFT JOIN yourTable ln ON fn.someCol = ln.someCol AND ln.columnName = 'LastName' LEFT JOIN yourTable an ON fn.someCol = an.someCol AND an.columnName = 'AccountNumber' WHERE fn.columnName = 'Firstname';
The above is the detailed content of How to Efficiently Convert Rows to Columns in SQL Server?. For more information, please follow other related articles on the PHP Chinese website!

This article explores optimizing MySQL memory usage in Docker. It discusses monitoring techniques (Docker stats, Performance Schema, external tools) and configuration strategies. These include Docker memory limits, swapping, and cgroups, alongside

This article addresses MySQL's "unable to open shared library" error. The issue stems from MySQL's inability to locate necessary shared libraries (.so/.dll files). Solutions involve verifying library installation via the system's package m

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

This article compares installing MySQL on Linux directly versus using Podman containers, with/without phpMyAdmin. It details installation steps for each method, emphasizing Podman's advantages in isolation, portability, and reproducibility, but also

This article provides a comprehensive overview of SQLite, a self-contained, serverless relational database. It details SQLite's advantages (simplicity, portability, ease of use) and disadvantages (concurrency limitations, scalability challenges). C

This guide demonstrates installing and managing multiple MySQL versions on macOS using Homebrew. It emphasizes using Homebrew to isolate installations, preventing conflicts. The article details installation, starting/stopping services, and best pra

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


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

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

SublimeText3 English version
Recommended: Win version, supports code prompts!

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools
