I have a table like this
and i want a 1 query that reference_id = 1 and reference fields equal to title and alias and introtext
expected result:
title -> හැඳින්වීම
alias -> overview-si
introtext ->ධීවර
is it possible? and how can I get it ?
if you have refence id and that three reference_field values, use
SELECT reference_field,value FROM tbl_name WHERE reference_id=1 AND ( reference_field='title' OR reference_field='alias' OR reference_field='introtext)
Related
I apologize if this is a simple question - I had some trouble even formatting the question when I was trying to Google for help!
In one of the tables I am working with, there's data value that looks like below:
Invoice ID
Status
Product List
1234
Processed
[{"product_id":463153},{"product_id":463165},{"product_id":463177},{"pid":463218}]
I want to count how many products each order has purchased. What is the proper syntax and way to count the values under "Product List" column? I'm aware that count() is wrong, and I need to maybe extract the data from the string value.
select invoice_id, count(Product_list)
from quote_table
where status = 'processed'
group by invoice_id
You can use a JSON function named: json_array_length and cast this column like a JSON data type (as long as possible), for example:
select invoice_id, json_array_length(Product_list::json) as count
from quote_table
where status = 'processed'
group by invoice_id;
invoice_id | count
------------+-------
1234 | 4
(1 row)
If you need to count a specific property of the json column, you can use the query below.
This query solves the problem by using create type, json_populate_recordset and subquery to count product_id inside json data.
drop type if exists count_product;
create type count_product as (product_id int);
select
t.invoice_id,
t.status,
(
select count(*) from json_populate_recordset(
null::count_product,
t.Product_list
)
where product_id is not null
) as count_produto_id
from (
-- symbolic data to use in query
select
1234 as invoice_id,
'processed' as status,
'[{"product_id":463153},{"product_id":463165},{"product_id":463177},{"pid":463218}]'::json as Product_list
) as t
I am trying to update a column in one database with a query:
Here the query
and this is the output i think it is impossible to asign a query to a field but what is the solution for that plz.
enter image description here
= can be used when we are pretty sure that the subquery returns only 1 value.
When we are not sure whether subquery returns more than 1 value, we will have to use IN to accommodate all values or simply use TOP 1 to limit the equality matching to one value:
UPDATE mascir_fiche SET partner = (SELECT TOP 1 id FROM hr_employee WHERE parent_id IN (SELECT id FROM hr_employee));
With Limit:
UPDATE mascir_fiche SET artner = (SELECT id FROM hr_employee WHERE parent_id IN (SELECT id FROM hr_employee) limit 1);
I have a details table with adeet column defined as jsonb[]
a sample value stored in adeet column is as below image
Sample data stored in DB :
I want to return the rows which satisfies id=26088 i.e row 1 and 3
I have tried array operations and json operations but it does'nt work as required. Any pointers
Obviously the type of the column adeet is not of type JSON/JSONB, but maybe VARCHAR and we should fix the format so as to convert into a JSONB type. I used replace() and r/ltrim() funcitons for this conversion, and preferred to derive an array in order to use jsonb_array_elements() function :
WITH t(jobid,adeet) AS
(
SELECT jobid, replace(replace(replace(adeet,'\',''),'"{','{'),'}"','}')
FROM tab
), t2 AS
(
SELECT jobid, ('['||rtrim(ltrim(adeet,'{'), '}')||']')::jsonb as adeet
FROM t
)
SELECT t.*
FROM t2 t
CROSS JOIN jsonb_array_elements(adeet) j
WHERE (j.value ->> 'id')::int = 26088
Demo
You want to combine JSONB's <# operator with the generic-array ANY construct.
select * from foobar where '{"id":26088}' <# ANY (adeet);
I am creating a viewer for PostgreSQL. My SQL needs to sort on the type that is normal for that column. Take for example:
Table:
CREATE TABLE contacts (id serial primary key, name varchar)
SQL:
SELECT id::text FROM contacts ORDER BY id;
Gives:
1
10
100
2
Ok, so I change the SQL to:
SELECT id::text FROM contacts ORDER BY id::regtype;
Which reults in:
1
2
10
100
Nice! But now I try:
SELECT name::text FROM contacts ORDER BY name::regtype;
Which results in:
invalid type name "my first string"
Google is no help. Any ideas? Thanks
Repeat: the error is not my problem. My problem is that I need to convert each column to text, but order by the normal type for that column.
regtype is a object identifier type and there is no reason to use it when you are not referring to system objects (types in this case).
You should cast the column to integer in the first query:
SELECT id::text
FROM contacts
ORDER BY id::integer;
You can use qualified column names in the order by clause. This will work with any sortable type of column.
SELECT id::text
FROM contacts
ORDER BY contacts.id;
So, I found two ways to accomplish this. The first is the solution #klin provided by querying the table and then constructing my own query based on the data. An untested psycopg2 example:
c = conn.cursor()
c.execute("SELECT * FROM contacts LIMIT 1")
select_sql = "SELECT "
for row in c.description:
if row.name == "my_sort_column":
if row.type_code == 23:
sort_by_sql = row.name + "::integer "
else:
sort_by_sql = row.name + "::text "
c.execute("SELECT * FROM contacts " + sort_by_sql)
A more elegant way would be like this:
SELECT id::text AS _id, name::text AS _name AS n FROM contacts ORDER BY id
This uses aliases so that ORDER BY still picks up the original data. The last option is more readable if nothing else.
I want to display the contents of the aggregated columns that is part of group by sql statement.
Example:
SELECT Shippers.ShipperName,COUNT(Orders.OrderID) AS NumberOfOrders FROM Orders
WHERE Orders.ShipperID=Shippers.ShipperID
GROUP BY ShipperName
In the above example the output gives me count as one of the result, whereas i need the aggregated orders.orderID actual values even. So say if one result count shows me 2. I need to know what are those two values which have been grouped. This result should be as another column in the same table.
try this with GROUP_CONCAT
SELECT Shippers.ShipperName,COUNT(Orders.OrderID) AS NumberOfOrders , array_agg(Orders.OrderID) as which_are_those FROM Orders
WHERE Orders.ShipperID=Shippers.ShipperID
GROUP BY ShipperName
array_agg returns an array, but you can CAST that to text and edit as needed (see clarifications, below).
Prior to version 8.4, you have to define it yourself prior to use:
CREATE AGGREGATE array_agg (anyelement)
(
sfunc = array_append,
stype = anyarray,
initcond = '{}'
);
or simply this:
SELECT Shippers.ShipperName,COUNT(Orders.OrderID) AS NumberOfOrders , string_agg(Orders.OrderID, ',') as which_are_those FROM Orders
WHERE Orders.ShipperID=Shippers.ShipperID
GROUP BY ShipperName