Questions tagged [array]
An array is an ordered linear data structure consisting of a collection of elements (values, variables, or references), each identified by one or more indexes. When asking about specific variants of arrays, use related tags as well. When using this tag, in a question that is specific to a database, tag the question with the database being used.
323 questions
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SELECT with array values on WHERE using postgres
I'm using an query to update a object array inside a jsonb column.
Example data:
[
{
"_id": "68696e0a3aab2f9ff9c40679",
"altura": 1,
"comprimento":...
- 145
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97
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Finding the distinct values in an array of documents
I've got a database full of documents which each contain a collection of transactions:
[
{
"key": 1,
"data": [
{
"trans": 1,
"uid&...
- 13
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143
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Cardinality of a multirange? How many ranges or gaps are there in a multirange?
How do I obtain the cardinality of a multirange?
I'm using range_agg() to aggregate ranges, which merges ranges if they are continuous, or returns what looks like an array of ranges if the ranges are ...
- 9,520
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PostgreSQL variadic array of arrays of composite type
I want to write a function that accepts array of arrays of my composite type. because of they have different lengths, it can NOT be defined as one array. So, I want to use variadic to accept arrays ...
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2
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Is there a way to "rearrange" arrays when selecting?
I have a table post_likes with one column being a post ID (uint), and another column being an array of IDs (uint[]) of users who liked the post.
If I'm selecting info from multiple tables on multiple ...
- 107
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108
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Index use after unwind in aggregate
We have a collection in our MongoDB where due to a changed use-case a so-far small query is now really slow. The aggregate in question is somewhat like this:
db.collection.aggregate([
{
$match: {...
- 5
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116
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What are downsides of using composite types and array type columns in TimescaleDB hypertable?
I'm considering to use a composite type, array of standard type and array of composite type columns in TimescaleDB hypertable. I'm curious whether using such columns has any downsides like less ...
- 101
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MongoDB createIndex compound unique index on array field
I'm trying to create a unique index in MongoDB that enforces uniqueness based on the existence and non-undefined nature of a field (barcodes) in my skus collection. Here's the index creation query I'm ...
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1
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129
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MySQL Trigger updating second table based on History and computed values
The Goal:
Update an secondary table called Lottery_Cycle when an INSERT occours on table Lottery_History with some computed values and checking previous data.
Let's say a lottery with 25 numbers of ...
- 11
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287
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An alternative to PostgreSQL union?
In the following example variables in single quotes '' are arguments passed to the PostgreSQL query. If 'tag_args' is an empty array, the first row of result table is a row of three nulls and I use ...
- 133
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Replacing substrings in array elements
I have a table with an array of URLs in column urls. Now there's a need to update some URLs changing the hostname. E.g.:
{https://storage.host1.com/file.jpg, https://storage.host1.com/file2.jpg}
...
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396
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Performance issues with @> operator in postgres 14
CREATE TABLE public.article (
id uuid NOT NULL,
tags _text NULL,
CONSTRAINT article_pkey PRIMARY KEY (id)
);
I have the requirement to load articles that have a tag which is in a large ...
- 25
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48
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How can I get a linear forecast in BigQuery?
BigQuery has no native support for linear forecasting outside of machine learning, but it does support user-defined functions, and these can accept arrays as inputs. However, (as of 2023/10 anyway), ...
- 5,985
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725
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Convert PostgreSQL array type
Given an enum type (e.g. letter).
What is the syntax to convert an existing array to the enum type? The existing values are valid for the enum. For example, how would I convert letter_data in:
create ...
- 115
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How to calculate quantity based on a boolean field and retrieve values from a JSON field in MySQL
I'm working with a table called price_options that has the following fields: id, slots, list_slots, and quantity.
Issue Description
My objective is to calculate the quantity for each price option ...
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