Category Archives: postgresql

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

PostgreSQL – DISTINCT Keyword The PostgreSQL DISTINCT keyword is used in conjunction with SELECT statement to eliminate all the duplicate records and fetching only unique records. There may be a situation when you have multiple duplicate records in a table. While fetching such records, it makes more sense to fetch only unique records instead of […]

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

PostgreSQL – HAVING Clause The HAVING clause allows us to pick out particular rows where the function”s result meets some condition. The WHERE clause places conditions on the selected columns, whereas the HAVING clause places conditions on groups created by the GROUP BY clause. Syntax The following is the position of the HAVING clause in […]