1.19. SQLite Delete statement

发布时间 :2025-10-25 12:31:14 UTC      

SQLite Of DELETE The query is used to delete existing records in the table. You can use the WHERE Of the clause DELETE Query to delete the selected row, otherwise all records will be deleted.

1.19.1. Grammar

With WHERE Of the clause DELETE The basic syntax of the query is as follows:

DELETE FROM table_name
WHERE [condition];

You can use the AND Or OR Operator to combine N quantity conditions.

1.19.2. Example

Hypothetical COMPANY The table has the following records:

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
1           Paul        32          California  20000.0
2           Allen       25          Texas       15000.0
3           Teddy       23          Norway      20000.0
4           Mark        25          Rich-Mond   65000.0
5           David       27          Texas       85000.0
6           Kim         22          South-Hall  45000.0
7           James       24          Houston     10000.0

Here is an example that removes a customer with an ID of 7:

sqlite> DELETE FROM COMPANY WHERE ID = 7;

Now, the COMPANY table has the following records:

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
1           Paul        32          California  20000.0
2           Allen       25          Texas       15000.0
3           Teddy       23          Norway      20000.0
4           Mark        25          Rich-Mond   65000.0
5           David       27          Texas       85000.0
6           Kim         22          South-Hall  45000.0

If you want to start from COMPANY If you delete all records from the table, you do not need to use the WHERE Clause, the query DELETE is as follows:

sqlite> DELETE FROM COMPANY;

Now, there are no records in the COMPANY table because all records have been passed DELETE Statement is deleted.

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.