Questions tagged [array]
The array tag has no usage guidance.
0
votes
1answer
11 views
Join on unnested integer array column and count occurrences in array
I am trying to join two tables after I have unnested one of them. The tables are:
CREATE TABLE teachers (id SERIAL, first_name VARCHAR(60), last_name VARCHAR(60));
CREATE TABLE training_modules (id ...
0
votes
1answer
24 views
postgres: using unnest in multiple rows
I have an array column containing information like
{a,b,c,a}
{a,b,a,b}
{b,a,a,b}
I want to run unnest on this array column, get the occurence of of each character.
a 2
b 1
c 1
a 2
b 2
b 2
a 2
I ...
0
votes
1answer
13 views
SQLite return sum of duplicate rows based on array
If I have a simple table fruits that looks like this:
+---+---------+------+
| | name | lbs |
+---+---------+------+
| 1 | apple | 0.25 |
| 2 | melon | 3.00 |
+---+---------+------+
In a ...
0
votes
0answers
36 views
How to pass array of UUIDs *OR* empty array and return implicit (inner join)?
How would I pass a list that is either full of UUIDs or empty, then return only joined records with those id values or all records if empty?
This question (Casting an array of texts to an array of ...
1
vote
2answers
23 views
uniqueness in array column type throughout all records
There is a table
id serial primary key,
names varchar(20)[]
it contains such record
1, {"one", "two", "three"}
Then, next record is inserting (notice one array element already exists in existing ...
1
vote
2answers
46 views
Removing values from array in postgreSQL
Lets say I have a table called users, who looks something like the following:
users table:
|user_id | name |
1 Bob
2 Alice
3 Joe
4 Tom
And ...
0
votes
0answers
10 views
How to always select records in array or empty array
I have a field records of jsonb[] type and I need to insert records from other tables(has many relation) whenever there is an update via trigger. When I apply select
SELECT INTO records * FROM "...
1
vote
2answers
16 views
How can I find all rows that have at least one element in an array matching a pattern? [duplicate]
Consider the following example:
CREATE TEMPORARY TABLE testing (
names TEXT[]
);
INSERT INTO testing VALUES
('{toplevel1}'),
('{toplevel1.sub1, toplevel2.sub2}'),
('{toplevel1.sub1....
0
votes
2answers
101 views
How to group multiple ROW as ARRAY
This is my current Query:
SELECT innings_no,
Player_Name,
sum(NoBalls) as NB
FROM (
SELECT A.innings_no,
A.bowler,
...
0
votes
1answer
30 views
Using postgres to select a filtered array
I'm looking to select data from a table that contains an ID, and an array of values. But in the query results, i want to filter the array and remove values that overlap with a white list.
For ...
0
votes
1answer
180 views
Postgresql: How to store high-dimensional ( N > 100) vectors and index for fast lookup by cosine similarity?
I am trying to store vectors for word/doc embeddings in a postgresql table, and want to be able to quickly pull the N rows with highest cosine similarity to a given query vector. The vectors I'm ...
1
vote
1answer
421 views
Extract JSON array of numbers from JSON array of objects
I have a table containing a json array of objects similar to this:
id | record
____________________
name1 | [{"a":0, "b":x}, {"a":1, "b":y}, {"a":2, "b":z}, ...]
I would like to get a table ...
2
votes
2answers
584 views
Get the max value from a slice of a JSON Array?
I would like to get the max value within a slice of a Json object (typicaly [1,2,3,5,6,7,9,10]) which is contained in a field named Data of the table raw.
The limits Start & End of the slice are ...
1
vote
1answer
24 views
Better way to select a matching subset of rows?
DB Fiddle link. I have a many to many table like this:
CREATE TABLE house_to_cats (
id SERIAL PRIMARY KEY,
house_id INTEGER,
cat_id INTEGER
);
-- house with cats 1 and 2: too small
INSERT INTO ...
0
votes
1answer
25 views
Removing duplicate-ish paths generated from recursive CTE
I have some multi-parented data, that I run a recursive CTE against to find common ancestors:
item_id |item_name |path_name |id_path_array |
--------|----------|-------------|--------------|
1 ...
1
vote
1answer
119 views
How can I get a unique array in PostgreSQL?
The following
SELECT ARRAY[a,b,c,d]
FROM ( VALUES
('foo', 'bar', 'foo', 'baz' )
) AS t(a,b,c,d);
Returns {foo,bar,foo,baz} of type text[]. I would like to get {foo,bar,baz} of type text[] with one ...
0
votes
1answer
45 views
Mongodb what is the cost of array queries?
As far as I can tell, find queries in mongodb involving an array appear very expensive. Take as example the queries given in: https://docs.mongodb.com/manual/tutorial/query-array-of-documents/
db....
0
votes
1answer
60 views
How do I modify a JSON object?
I have a table "raw_data" in which I have a field "data" containing a json array like:
{'a' : 1,
'b' : 2,
'c' : 3}
I would like two different things:
Append a new item like {'d' : 4} at the end of ...
1
vote
1answer
264 views
How to pass an array to a plpgsql function with VARIADIC parameter
I am trying to define a plpgsql function in Postgresql 10 with several parameters, including an array.
I have already defined the function
CREATE OR REPLACE FUNCTION mix_table_fields(...
0
votes
2answers
72 views
PostgreSQL - how to generate an array containing column name and column data…?
I'd like to create a dictionary - an array - from a simple query, to include column names in output.
IE, I'd like to turn this:
SELECT id, last, first FROM names;
id | last | first
---...
2
votes
3answers
119 views
Pass array of mixed type into stored FUNCTION
I am preparing procedure, that is basically finishing payment. It takes all info as arguments and do all inserts and stuff in one transaction.
the problem here is, that one argument is list of n ...
1
vote
1answer
73 views
How to prepend an element to a JSON array?
I have a plpgsql function in PostgreSQL 9.6, which at some point has a text variable _x (guaranteed to not be NULL) and another variable _y which is a JSONB array of text (which might be empty).
How ...
1
vote
3answers
1k views
How to select multiple values into an array and loop through? (postgres 9.3)
I have simple table for the sake of argument. I have a function that selects ids and loops through them called loop_test. I can select an array of ids and loop through them, causing my changes in a ...
2
votes
2answers
2k views
Casting an array of texts to an array of UUIDs
How can I cast an array of texts into an array of UUIDs?
I need to do a join between two tables: users and projects.
The users table has an array field named project_ids containing the project IDs ...
0
votes
1answer
110 views
Use an array returned from a subquery as argument in WHERE clause with ANY function in outer query
A query like this:
SELECT *
FROM person
WHERE person.favorite_number = ANY(
ARRAY[ 2 , 3 ]
)
;
…runs. The ANY() function tells us if the single value is found within an array of values. So, ...
3
votes
4answers
144 views
Representing lists in SQL
My database setup is modern (My)SQL.
I've got a Content Table, including ids.
Now, users should be able to comment on content.
To achieve this, arrays have come to my mind.
Now I see several options ...
0
votes
1answer
223 views
Index for split string. PostgreSQL 10
I have the following string in db:
A/B/C/
A/B/D/
E/F/C/
It's the uri column.
The table is the following:
create table meta_info (
id bigserial primary key,
uri varchar,
created ...
1
vote
1answer
30 views
How can I index a text[] field in postgresql?
I have two columns:
alternate_names text[]
first_name character varying
I am not sure how I can write an index on this type of query?
SELECT "people".* FROM "people"
WHERE (lower(first_name) = '...
1
vote
1answer
1k views
How can you insert data into a ARRAY column on a Snowflake table using SQL?
I am having difficultly finding documentation on how to insert data into an ARRAY column type using SQL on a Snowflake table.
Snowflake Documentation: https://docs.snowflake.net/manuals/sql-reference/...
1
vote
2answers
47 views
How do You concatenate a value to an array that was retrieved through a query in sql?
I have a table named "mkvtable" that establishes a correspondence between individual strings and arrays of strings:
word | mkvword
---------+-----------------
hello | {world,friend}
...
2
votes
1answer
548 views
Error while inserting into array of timestamps
Im using postgres 10.1 and the Datestyle config is the following
DateStyle
-----------
ISO, MDY
Im having this error
ERROR: date/time field value out of range: "1535673858" Hint: Perhaps
you ...
0
votes
1answer
168 views
Postgresql JSONB Column, how to query for multiple specific elements in a JSON array
Giving the following JSONB data structure of a stopInfo column in a myTable table:
{
"stopInfo": [
{
"stopType": "Origin",
"partnerId": "KR01",
"locationId"...
0
votes
1answer
41 views
What is the best way to manage interdependent indexes
So I have a table of items as so
|firstIndex|subIndex|relatedIndexes|
-----------------------------------
| 1 | 1 | 2 ,6 , 8 |
-----------------------------------
| 1 | 2 |...
0
votes
1answer
54 views
Storing arrays of data in a time-series database
I'm building an low utilization time-series database to capture yearly data points for a set of items fewer than 100,000.
My question has to do with storing arrays of data in a way that is easily ...
2
votes
0answers
96 views
Copy to file and transform arrays
I'm copying data from a Postgres DB on AWS RDS to a Postgres-like DB on AWS Redshift.
Varchar arrays are being exported as {foo,bar} but Redshift wants them as ["foo","bar"].
Redshift doesn't ...
1
vote
1answer
22 views
extract different number of rows from multiple tables
I have a quick question. I'm looking for the concept behind this, not necessarily a ready-to-use code, but if it's not too complex, I don't mind a quick solution. I have an app that manages accounts. ...
1
vote
0answers
49 views
Postgresql 10 arrays equality failure
I am using AWS RDS postgres instance version 10.3.
Completly stuck with the problem.
I have a table like:
create table social_message(
social_profile_id int8 not null,
body text,
subject ...
2
votes
1answer
2k views
What is the fastest way to verify that a json[] array is not empty?
I want to verify that an json[] column the_array is not empty. For a normal array, I could check on:
the_array != '{}'
However, that does not work for a json[], as demonstrated below:
select '{}'::...
3
votes
1answer
801 views
Use array_position() function to get the most frequent value for column from pg_stats
I'm trying to execute this simple query in order to check whether some value (1000) belongs to MCV list used by Postgres query optimizer:
SELECT array_position(most_common_vals, 1000)
FROM pg_stats
...
2
votes
1answer
260 views
How to remove duplicates from any array and preserve ordering in PostgreSQL?
I'm looking for a way to eliminate duplicates from a PostgreSQL array
while preserving the ordering of its elements. What I currently
have are the following functions:
create function array_unique( ...
1
vote
2answers
6k views
POSTGRES declaring variable containing date array in functions
I am trying to declare a date array.
I have tried this:
DECLARE
dateVal DATE[] := ['2018-01-01','2018-02-01'];
I get:
ERROR: syntax error at or near "["
How do I properly declare it?
4
votes
3answers
4k views
How to unnest and GROUP BY elements of a JSON array?
Given the band table, with a json column holding an array :
id | people
---+-------------
1 | ['George', 'John']
2 | ['Thomas', 'James']
3 | ['James', 'John']
How to list the number of bands each ...
0
votes
0answers
578 views
Convert JSON array to native integer array
My function is returning json data which is containing two integer array.
Now I need to get this two integer array list and passed it to another function.
CREATE OR REPLACE FUNCTION method1(id ...
1
vote
1answer
174 views
Have several 128 elements lists, need to obtain distance between them
Is storing them in a CUBE type field and then getting euclidean distance, (using <->) the only way?
I can not save them as a list of floats, since i get: "can't adapt type numpyndarray"
Can ...
2
votes
2answers
90 views
Testing if an element in a PostgreSQL array?
Is there an operator in PostgreSQL to test whether an element is in an array?
Currently, I'm doing such tests in a slightly complex way by first constructing a singleton array for the element and ...
0
votes
1answer
518 views
how do you output a plsql array via ref cursor
I have a legacy procedure that returns a plsql assoc table to a C++ DLL. Now I need to call it via C# and ODP.NET. I have been unable to find any info on how to call a proc that returns a pl/sql ...
0
votes
0answers
275 views
MySQL version of split_to_array or split_to_table?
PostgreSQL supports two String Functions, that are incredibly useful
regexp_split_to_array
regexp_split_to_table
Both of these functions essentially take two strings, (a) a pattern and (b) an input ...
1
vote
2answers
1k views
Loop through slices of 2-dimensional array in plpgsql function?
How to loop through an array of arrays in a function and access its elements?
Below is the the function (this is only the relevant part).
create or replace function public.whatwhatwhy(
...
6
votes
1answer
769 views
ORDER BY gives ERROR: function array_position(text[], character varying) does not exist
I have a pretty basic categorical column in a Postgres database that is currently stored as VARCHAR. I can select a count of each with:
I though adding an ORDER BY array_position() would do it:
...
1
vote
1answer
2k views
Store arrays in table
I'm not sure if this is the best SE section to ask my question. If not, I kindly ask you to help me to find out the best one.
Developing a web application in php and MySql I'm in doubt how to store a ...
