Relational Operator - Join

Relational Algebra Between Sql And Query Plan

About

join is a relational operator that pair tuples (row) of two relations (table, …) according to a condition (predicate).

Notation

Relational

<MATH> \LARGE R_1 \bowtie_c R_2 </MATH> where:

SQL

See SQL - Joins (Home)

Symbol

Type Symbol Unicode Point Latex
Join <math>\Join</math> 2A1D \Join
Left Outer Join ⟕ 27D5 \leftouterjoin
Right Outer Join ⟖ 27D6 \rightouterjoin
Full Outer Join ⟗ 27D7 \fullouterjoin

Rule

<MATH> \LARGE R_1 \bowtie_{ predicate } R_2 = \sigma_{ predicate } ( R_1 \times R_2 ) </MATH> which means:

is the same than

Type

Logical

Short hand:

Implementation




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