I am a CTO with over 5 years of experience in start-up and over 10 years in working at managing position for big companies. I am also a full-stacks developer with over 12 years in system design, product development and technology product deployment.User experience and system security are the things I care about most.
Articles By This Author
Solving SQL Server Connection Problem
Inspect Server Settings
There are three significant aspects that users may neglect, which lead to the failure of the connection to the SQL Server.
Enable TCP/IP Connection
To check whether your server enabled to TCP/IP connections:
Uninstall Oracle DB on Windows completely
Manually
- START -> RUN -> Services.msc
- Locate all Ora* services & click on STOP
- Start -> RUN -> Regedit
- Locate HKEY_LOCAL_MACHINE folder in the registry
- Open Software folder
- Delete the Oracle folder under Software
- Open System folder in HKEY_LOCAL_MACHINE
- Open CurrentControlSet folder within the System folder
- Open Services
- Delete all keys related to Oracle. Every key starts with “ORA..”
- Close the regedit
- Delete ORACLE_HOME folder
- Delete the Oracle folder in Program Files
- Reboot
Uninstall all Oracle components using the Oracle Universal Installer (OUI).
Grant privilege on all objects in a Schema to a user in Oracle Database
In this example I have given select on all tables in schema test1 to user test2. As well grant all DML privilege on tables and views, and grant execute on procedures, functions and packages in a schema test1 to user test2.
SQL> create user test1 identified by test1; User created. SQL> grant connect,resource to test1; Grant succeeded. SQL> create user test2 identified by test2; User created. SQL> grant connect,resource to test2; Grant succeeded. SQL> conn test1/test1 Connected. SQL> create table test_table1(id number,name varchar2(30)); Table created. SQL> create table test_table2(id number,name varchar2(30)); Table created. SQL> show user; USER is "TEST1"
If you want to grant select privilege:
Oracle database Commands
SSH vào server bằng tài khoản oracle.
Truy cập công cụ sqlplus, đăng nhập quyền sysdba:
sqlplus / as sysdba
Thông thường, có thể lệnh sqlplus có thể sẽ không tồn tại trong session hiện tại, bạn cần thực hiện câu lệnh sau để áp dụng biến môi trường (xem trong bài Install Oracle 11g R2 on CentOS):
Install Oracle 12c R2 on CentOS
Cài đặt GUI
Đầu tiên cần cài đặt giao diện GUI cho CentOS, làm theo bài hướng dẫn sau: Install Gnome 3 GUI on RHEL, CentOS
Download bộ cài
Download bộ cài Oracle 12c từ trang chủ của Oracle hoặc bằng link Google Drive tại đây:
Install Oracle 11g R2 on CentOS
Cài đặt GUI
Đầu tiên cần cài đặt giao diện GUI cho CentOS, làm theo bài hướng dẫn sau: Install Gnome 3 GUI on RHEL, CentOS
Download bộ cài
Download bộ cài Oracle 11g từ trang chủ của Oracle hoặc bằng link Google Drive tại đây:
Backup MySQL database with mysqldump
Option 1: mysqldump an entire mysql instance
Everything written in one file: table structures, indexes, triggers, stored procedures, users, encrypted passwords. Other mysqldump options can also export different styles of INSERT commands, log file and position coordinates from binary logs, database creation options, partial data (–where option), and so forth.
mysqldump -h... -u... -p... --hex-blob --routines --triggers --all-databases | gzip > MySQLData.sql.gz
What to Do If You Forget Your Android Phone’s PIN, Pattern, or Password
Android secures your device by asking you for a PIN, pattern, or full password. What happens if you forget the security method you set up? If you’re lucky, you can get back in easily—but that may not be possible. Even if you use a fingerprint or Face Unlock to secure your Android phone, neither of […]