Breast cancer may cause swollen axillary lymph nodes since the lymph vessels of the breast drain into the lymph nodes of the armpit. These nodes become enlarged when cancer cells spread beyond the breast tissue.
Relational database. (Redirected from Database constraints) A relational database is a digital database whose organization is based on the relational model of data, as proposed by E. F. Codd in 1970. The various software systems used to maintain relational databases are known as a relational database management system (RDBMS).
A database lock is used to âlockâ some data in a database so that only one database user/session may update that particular data. So, database locks exist to prevent two or more database users from updating the same exact piece of data at the same exact time. database lock is used to âlockâ some data in a database so that only one database user/session may update that particular data. So, database locks exist to prevent two or more database users from updating the same exact piece of data at the same exact time.