The command to modify table data in SQL is UPDATE, and the syntax is UPDATE table_name SET column_name = new_value WHERE condition. Among them, table_name is the table name, column_name is the column name, new_value is the new value, and condition is the filter condition, used to specify which rows to update. Example: UPDATE customers SET age = 30 WHERE name = "John Doe", change the name column value in the customers table to "John D
Modify in SQL Table data commands
In SQL, you can use the UPDATE
command to modify the data in the table.
UPDATE
Syntax of the statement. is:
UPDATE table_name SET column_name = new_value WHERE condition;
where:
- ##table_name
is the name of the table where the data is to be updated.
- column_name
is the name of the table to be updated. The column name of the updated data.
- new_value
is the new value of the data to be updated.
- condition
is the condition used to filter the data, specified. Which rows to update.
Example
The following example will have the value of thename column in the
customers table. The
age column of the row for "John Doe" is updated to 30:
UPDATE customers SET age = 30 WHERE name = "John Doe";After executing this command, the value of the
name column in the
customers table The row for "John Doe" will be updated and the value of the
age column will become 30.
Note:
- UPDATE
The command will directly affect the data in the database, please use it with caution.
Make sure the conditions are correct, otherwise unnecessary data rows may be updated. - If the conditions are not specified, then All rows in the table will be updated.
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