Join (SQL)
An SQL join clause combines records from two or more tables in a database. It creates a set that can be saved as a table or used as is. A JOIN is a means for combining fields from two tables by using values common to each. ANSI standard SQL specifies four types of JOIN: INNER, OUTER, LEFT, and RIGHT. As a special case, a table (base table, view, or joined table) can JOIN to itself in a self-join.
A programmer writes a JOIN predicate to identify the records for joining. If the evaluated predicate is true, the combined record is then produced in the expected format, a record set or a temporary table.
Read more about Join (SQL): Sample Tables, Inner Join, Outer Joins, Merge Rows, Alternatives, Implementation
Famous quotes containing the word join:
“If your little savage were left to himself and be allowed to retain all his ignorance, he would in time join the infant’s reasoning to the grown man’s passion, he would strangle his father and sleep with his mother.”
—Denis Diderot (1713–1784)