Detailed explanation of MySQL database addition, deletion and modification operations

Inserting Data

insert into table name (column name 1, column name 2, column name 3) values ​​(value 1, value 2, value 3);

insert into user(user_id,name,age) values(1,'nice',24);

The simple way to write it is to omit the field name, but all fields must be inserted.

Batch Insert

Efficiency issues of single and batch insertion

The efficiency of inserting multiple records in MySQL is greater than that of inserting a single record.

Deleting Records

delete from table name [where condition]

If no conditions are specified, all data in the table will be deleted one by one.

What is the difference between delete and truncate?

delete: belongs to DML, deletes data in the table one by one

truncate: belongs to DDL, delete the table first and then rebuild it

Which one is more efficient in deleting data, delete or truncate?

If the data is small, delete is more efficient

If the amount of data is large, truncate is more efficient

Update Record

update table name set column name = column value, column name 2 = column 2 value [where condition]

Modify multi-field data

Modify all (use with caution)

The above is a detailed explanation and integration of the MySQL database addition, deletion and modification operations introduced by the editor. I hope it will be helpful to everyone. If you have any questions, please leave me a message and the editor will reply to you in time. I would also like to thank everyone for their support of the 123WORDPRESS.COM website!