Insert multiple rows into a table with id from other table if not exists...
I have done similar task where I can insert a row into a table if data doesn't exists:WITH user_exists AS ( Select id from users where username='%s' ), user_new AS ( INSERT INTO users (username) SELECT...
View ArticleHow to turn a set of flat trees into a single tree with multiple leaves?
We have this beautiful Postgres tree generator. Yet it kind of produces cuts of a tree not a whole tree all at once:item_id jsonb_pretty1 {"title": "PARENT","item_id": 1,"children": {"title": "LEVEL...
View ArticleFor each category, find the count of foreign-key items in all child...
I have a typical tree structure stored as an adjacency list in PostgreSQL 9.4:gear_category ( id INTEGER PRIMARY KEY, name TEXT, parent_id INTEGER );As well as a list of items attached to the...
View ArticleHow to eliminate duplicates made by recursive CTE [closed]
I have following schema in PostgreSQL 12 (objects and their relations are versioned by date ranges):CREATE TABLE tmp_deps ( id bigint, code text, name text, start_date date, end_date date);CREATE TABLE...
View ArticleCreate JSON object from recursive tree structure
Having this simple many-to-many self-referential structure.An item owns other items through the joins table:CREATE TABLE items ( item_id serial PRIMARY KEY, title text);CREATE TABLE joins ( id serial...
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Nested CTEs Returning Incorrect Results in Certain Situations
OK, first let me say I got this issue from:Seeking Tsql wrong join explantion in CTE [closed]I was trying to assist to figure out the issue, but got stumped when trying to debug the code one step at a...
View ArticleHow can a cheap function in a SELECT make the whole query slow?
I'm using Postgres 13.3 with inner and outer queries that both only produce a single row (just some stats about row counts).I can't figure out why Query2 below is so much slower than Query1. They...
View ArticleUnrecognized configuration parameter when using set_config(text, text,...
I'm trying to implement a simple ABAC system using row level security, with main policy defined as following:CREATE policy resource_access ON resourceUSING ( ( org_id::varchar =...
View ArticleWhy my not-null columns become nullable in my CTE recursive query?
I have a simple hierarchical table. Let's say it has these columns:Id, [Guid], ParentId, TitleOnly ParentId is nullable. Other columns are not nullable.I have created a recursive query to show me the...
View ArticleSQL Server CTE Bottom to Top Recursive with Where clause
I have an Employee Table with an EmployeeId, ManagerId and a Name field.The goal is to make a recursive With fetching all the rows from an employee to the top manager (ManagerId is null).I found this...
View ArticleSELECT... with LIMIIT, but iterate forward getting other records?
I am doing a SELECT * FROM... with LIMIT query inside of a LOOP in my pgplsql function/procedure - something like this, e.g.$$DECLAREBEGINLOOP exit when get diagnostics n_rec_count = 0; WITH cte_table...
View ArticleSlow CTE update query
I have a query that is running for more than three hours without completing.I realized that the bad part is the Filter operator which has a cost of 89%.WITH FASES_NUMERADAS_CTE AS ( SELECT NUM_PROCES,...
View ArticleUpdate rows based on a recursive CTE query result
This query shows all lines recursively based on a uuid / parentUUID relationship:WITH RECURSIVE files_paths (id, parent) AS( SELECT uuid, parentuuid FROM core_data WHERE uuid =...
View ArticleHow to use a recursive CTE to get ancestors in a hierarchy
create table division ( id serial primary key, name varchar not null);-- nested sets tablecreate table location ( id serial primary key, name varchar not null, division_id integer not null references...
View ArticleHow to create temp tables using CTE in Redshift
Below query is working fine in PostgreSQL, however, returning error in Redshift -create temp table sample_data aswith input_values1 (Name) as( values ('A'), ('B'), ('C'), ('D'), (null)) select * from...
View ArticleMariaDB: No database selected error on some query [migrated]
I have a php code that rise a query against a MariaDB (using MariaDB 10.5.11 on debian 11) table; I use php-mysql prepared queries for this task as reported in the code...
View ArticleMYSQL Error 1064 on INSERT INTO with CTE
I am trying to write a stored procedure to return a calculated value from a dataset by writing the result to a table. When I run this code on MySQL 8.0.32, I get an error 1064 Syntax error on the...
View ArticleOptimizing a recursive CTE or replacing it with a temporary table
I have a recursive query like this:with recursive PCte(id) as ( select p1.id from Product p1 where p1.parent_id is null and p1.serial_number in ('123', '124','125', 'n') union all select p2.id from...
View ArticleJOIN vs WITH differences
apologize if there is the same question.When I started my career, my manager told me that you don't need to use "WITH", you can do anything with "JOIN".Now I am wondering is it any performance...
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Improving query (Doing a nasty self join on a range with ctes)
-- The CTE1 is just to create columns that dictate the bound of what is considered the same entry-- Also I do a dense rank by ACT_TIME, and a PARITION BY on ID1, ID2-- so all ID1/ID2 combos are ranked...
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