Stack Overflow
Stack Overflow

Questions tagged [anti-join]

An anti-join, also called an excluding-join or left-outer-join, comes from requesting data from a table where some value is not in another table

Formal Definition

The antijoin, written as R ▷ S (where R and S are relations), is similar to the semijoin, but the result of an antijoin is only those tuples in R for which there is no tuple in S that is equal on their common attribute names.

Venn Diagram

anti-join

SQL Phrasing

SELECT <select_list>
FROM TableA A
LEFT JOIN TableB B
ON A.Key = B.Key
WHERE B.Key IS NULL

Related to

References:

78 questions
3
votes
1 answer

R tidytext stop_words are not filtering consistently from gutenbergr downloads

This is a bizarre puzzle. I downloaded 2 texts from gutenbergr - Alice in Wonderland and Ulysses. The stop_words disappear from Alice but they are still in Ulysses. This issue persisted even when replacing anti_join with filter (!word %in%…
Regis Maria O'Connor
  • 43
  • 5
3
votes
1 answer

Performing a semi-anti-join (in binary search)

I'd like to subset a data.table by choosing the first key and excluding the second key. set.seed(18032) DT <- data.table(grp1 = sample(10, 1000, T), grp2 = sample(10, 1000, T), v = rnorm(100), key = "grp1,grp2") My…
MichaelChirico
  • 33,841
  • 14
  • 113
  • 198
2
votes
1 answer

A MySQL query addressing three tables: How many from A are not in B or C?

I have a problem formulating a MySQL query to do the following task, although I have seen similar queries discussed here, they are sufficiently different from this one to snooker my attempts to transpose them. The problem is (fairly) simple to…
Frankie
  • 596
  • 3
  • 24
2
votes
5 answers

Using information from one table to find if the info exists in another table

I have 2 tables: ads : +------+---------------+ | ID | Name | +------+---------------+ | 1 | Item 1 | | 2 | Item 2 | | 3 | Item 3 | | 4 | Item 4 | | 5 | Item 5 …
Lee Price
  • 5,182
  • 11
  • 34
  • 36
2
votes
1 answer

Can't understand the mysql self left-join query

I come across a query which is, SELECT it1.survey_set_id, it1.type, it1.value FROM survey_condition_filter it1 LEFT JOIN survey_condition_filter it2 ON(it1.survey_set_id = it2.survey_set_id AND it2.type = 3002) WHERE it1.type IN (2000, 2001, 2002)…
Abhijith Ea
  • 115
  • 11
2
votes
2 answers

Anti_join between df1 and df2 but how to change all mismatch in df2 to NA

Below are my two dataframes, df1 and df2 df1 <-…
Catalyst
  • 426
  • 3
  • 12
2
votes
2 answers

Anti join followed by union in Spark SQL

I am running PySpark script in which I am doing anti join & union of 2 dataframes. But I want to do it in Spark SQL. df_src: +-------+-------+ |call_id|call_nm| +-------+-------+ | 100| QC| | 105| XY| | 110| NM| | 115| …
Shivika
  • 209
  • 3
  • 15
2
votes
2 answers

SQL antijoin with multiple keys

I'd like to implement an antijoin on two table but using two keys so that the result is all rows in Table A that do not contain the combinations of [key_1, key_2] found in Table B. How can I write this query in SQL?
mdrishan
  • 469
  • 3
  • 15
2
votes
2 answers

Finding row numbers which occur in on table but not in the second

I have two huge data frames where one table contains fewer observations. Anti-join from dplyr works perfect and fast, but I would to keep the original row names if possible. Any function/package which allows this with the speed of anti_join? My…
MLEN
  • 2,162
  • 2
  • 20
  • 36
2
votes
0 answers

How to stop anti_join from reversing sort order in R?

I have two sets of names that are ordered A-Z. I'm using anti_join to filter out whatever is present in the 2nd set. Example: library(dplyr) t1 <- data.frame(Name = state.name, Abbr = state.abb) t2 <- data.frame(Abbr = state.abb[50]) t3 <-…
armipunk
  • 458
  • 2
  • 13
1
vote
1 answer

Return anti-join of two data frames with values outside a certain percentage difference

I would like to compare two mixed-type data frames and return the rows that are different between them--but I would like numeric values to only be returned within a certain percentage. tbl1 <- tibble(var1 = c('r1', 'r2', 'r3', 'r4', 'r5'), …
JemJem
  • 25
  • 6
1
vote
1 answer

How to optimise anti-join SQL queries

I have a database table where each entry is a resource that can be used once by each user. Each user can only use resources that they have not already used, but the same resource can be used by different users, so if I'm not mistaken, the users and…
Danosaurus
  • 35
  • 4
1
vote
1 answer

Avoid data shuffle and coalesce-numPartitions is not applied to individual partition while doing left anti-join in spark dataframe

I have two dataframe - target_df and reference_df. I need to remove account_id's in target_df which is present in reference_df. target_df is created from hive table, will have hundreds of partitions. It is partitioned based on date(20220101 to…
Arvinth
  • 60
  • 6
  • 27
1
vote
1 answer

Pyspark: Comparing Datasets and Identify Unchanged Records

I am trying to implement a generic historization procedure for my data in PySpark. Those data have a key, several business information columns, and some additional technical metadata, which should not be considered for identifying changes, but…
Alfred G
  • 15
  • 5
1
2
3 4 5 6