What does value mean in mysql
VALUE keyword in MySQL: 1. Get column value: SELECT value FROM table_name WHERE column_name = value; 2. Set column value: UPDATE table_name SET column_name = value WHERE condition.
VALUE meaning in MySQL
VALUE is a keyword in MySQL, used to get or set a table The value in the middle column.
Get the column value
Use the VALUE keyword to get the value of the specified column in the table. The syntax is as follows:
<code>SELECT value FROM table_name WHERE column_name = value</code>
For example, to get the value of the row in the table named "users" where the "email" column is "john.doe@example.com", you can use the following query:
<code>SELECT value FROM users WHERE email = 'john.doe@example.com'</code>
Set column value
The VALUE keyword can also be used to set the value of a specified column in the table. The syntax is as follows:
<code>UPDATE table_name SET column_name = value WHERE condition</code>
For example, to update the value of the row whose "name" column is "John Doe" in the "users" table to "Jane Doe", you can use the following query:
<code>UPDATE users SET name = 'Jane Doe' WHERE name = 'John Doe'</code>
Note
- The VALUE keyword can only be used for a single column.
- The VALUE keyword cannot be used in subqueries or joins.
- The VALUE keyword has been deprecated in MySQL version 8.0, and it is recommended to use the "AS" keyword instead.
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