Questions tagged [join]
A JOIN is a general operation in relational algebra for a combining operation on two relations in a relational database system. JOIN is also a keyword of the SQL language for performing analogous SQL operations.
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Pyspark saveasTable gives error on overwrites for pyspark data-frame
In my Pyspark code I am performing more than 10 join operations and multiple groupBy in between. I want to avoid a large DAG and so I decided to save the dataframe as a table to avoid re-computations. ...
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Where to create Join entities in Clean Architecture .NET
I am developing an application with Clean Architecture and I came across a problem with the structuring and location of some Objects.
In my Application layer, I am using the CQRS approach. In one of ...
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How to display a one-to-many relationship in a column in JSON format
Table points has columns
point_id (int unsigned, auto_increment, primary key)
name (varchar(512))
Table filters has columns
filter_id (int unsigned, auto_increment, primary key)
label (varchar(128))...
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"no such table" error when attempting a join function with two different tables in sqflite
I'm having quite a few problems understanding how sqflite works.
I have the following "users" and "items" tables and their create method:
//tableName = "items"
Future<...
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R how to create a new dataframe with column values calculated from three other dataframes
I'm new to R and struggling to create a new dataframe where the values for multiple columns are created using values from columns with the same names from three other dataframes with the same ...
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OTBI Data Model Dataset Join [closed]
I am newly introduced to OTBI due to work (about 2 months ago). I have some SQL knowledge, but I am at a loss on how to join to datasets I have.
I want to list my budget and expenses (see screenshot) ...
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How to join all rows of one table to a column of another table that is not in the first table?
First table is only one column, just customer ID:
ID
___
1122
2222
3333
Second table is the product information:
| State| User | Limit
| CA | JM21 | 100
| OH | JD11 | 200
| ...
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Query Designer - SSRS Report - Restrict Parameters by Other Parameters
We have a report in SSRS build using query designer that lives on top of data that comes from the data warehouse. The set up looks like this.
How do I restrict one column by another column. Only ...
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Semi Complicated Join Query
I have a few tables that I need to join in a specific way to get the required results.
ACCOUNTS
This is the first table, I need to check every row in here to find the data I need, the relevant fields ...
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Python Pandas: Select matching value from other table with comparison into each row without matching key [duplicate]
I have a structure of events happening for entities in table A.
Each event is linked to a process in table B.
Unfortunately I don't have the process ID in table A only a timestamp. Table B includes ...
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Grails Lazy load to avoid Too many table issue after 61 tables to Join
I have a set of tables inherited from the parent table and finally got stuck with the SQL limitation of joining too many tables.
Too many tables; MySQL can only use 61 tables in a join. Stacktrace ...
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Joining lat/lon data frames by nearest distance
Let's say I have a regular latitude/longitude grid and data at irregular locations, like this:
grid = tidyr::crossing(lon = seq(0, 1, 0.25), lat = seq(0, 1, 0.25))
data = tibble::tibble(lon = runif(4),...
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Joining together 2 tables while joining one table twice with different filters
I have collected data in 2 SQL Server tables:
AREAS
area
a
b
SHIFTS
personal_id
date
shifttime
area
12
2012-01-10
early
a
13
2012-01-10
early
a
14
2012-01-10
late
a
15
2012-01-10
early
b
I ...
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Explain MySQL left join
CREATE TABLE tab1 (
id1 int NOT NULL,
field11 int NOT NULL,
field12 date NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;
INSERT INTO tab1 (id1, field11, field12) ...
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Joining and standardizing Country names in Tableau from different sources
I am calculating some metrics and need to standardize Country names on all sides in order to calculate it on a country level.
I have a transaction file consisting of two sql queries and external excel ...
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