Category Archives: postgresql

Khóa học miễn phí Date/Time Functions & Operators nhận dự án làm có lương

PostgreSQL – DATE/TIME Functions and Operators We had discussed about the Date/Time data types in the chapter . Now, let us see the Date/Time operators and Functions. The following table lists the behaviors of the basic arithmetic operators − Operator Example Result + date ”2001-09-28” + integer ”7” date ”2001-10-05” + date ”2001-09-28” + interval […]

Khóa học miễn phí PostgreSQL – Constraints nhận dự án làm có lương

PostgreSQL – CONSTRAINTS Constraints are the rules enforced on data columns on table. These are used to prevent invalid data from being entered into the database. This ensures the accuracy and reliability of the data in the database. Constraints could be column level or table level. Column level constraints are applied only to one column […]