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:
“I respect the ways of old folks, but the blood of a rooster or a goat cannot turn the seasons, change the course of the clouds and fill them up with water like bladders. The other night, at the ceremony for Legba, I danced and sang my fill: I am a black man, no? and I enjoyed it like a true Negro should. When the drums beat, I feel it in the pit of my stomach, I feel the itch in my hips and up and down my legs, I have got to join the party. But that is all.”
—Jacques Roumain (1907–1945)