4.2.15. MySQL UPDATE update

发布时间 :2025-10-25 12:31:20 UTC      

If we need to modify or update the data in MySQL, we can use the SQL UPDATE command to do so.

Grammar

The following is the general SQL syntax for the UPDATE command to modify MySQL data table data:

UPDATE table_name SET field1=new-value1, field2=new-value2
[WHERE Clause]
  • You can update one or more fields at once.

  • You can specify any condition in the WHERE clause.

  • You can update the data at the same time in a single table.

The WHERE clause is very useful when you need to update the data of a specified row in a data table.

Update data from the command prompt

Principles, Technologies, and Methods of Geographic Information Systems  102

In recent years, Geographic Information Systems (GIS) have undergone rapid development in both theoretical and practical dimensions. GIS has been widely applied for modeling and decision-making support across various fields such as urban management, regional planning, and environmental remediation, establishing geographic information as a vital component of the information era. The introduction of the “Digital Earth” concept has further accelerated the advancement of GIS, which serves as its technical foundation. Concurrently, scholars have been dedicated to theoretical research in areas like spatial cognition, spatial data uncertainty, and the formalization of spatial relationships. This reflects the dual nature of GIS as both an applied technology and an academic discipline, with the two aspects forming a mutually reinforcing cycle of progress.