Database Tips and Tricks

1. How to extract a string from CLOB datatype in SQL?

>dbms_lob.substr( clob_column, for_how_many_bytes, from_which_byte );

Using this function, we can extract a string.

2. How to copy database within same server?

1. Dump database objects and data into SQL file using the mysqldump tool. 

2. 1>mysqldump -u root -p <database_to_copy> > D:\Temp\<database_to_copy>.sql

2 Enter password: **********

3. >mysql -u root -p <New_database> < D:\Temp\<Copied_database>.sql 

2 Enter password: **********

2. How to copy database from server to another?

1 CREATE DATABASE <database_name>;
2
3 USE <database_name>;

1>mysql -u root -p <database_name> < D:\Temp\<database_to_copy>.sql