I have a query which gives me total 12408 records after executing but i want this give me total records as count column
select
c.complaint_id,c.server_time,c.completion_date,c.road_id,c.photo,c.dept_code,c.dist_code,c.eng_userid,c.feedback_type,c.status,p.dist_name,p.road_name,p.road_dept,e.display_name,e.mobile
from complaints as c INNER JOIN pwd_roads as p ON p.road_id=c.road_id
INNER JOIN enc_details as e ON CAST(e.enc_code as INTEGER) = p.enccode
where c.complaint_id=c.parent_complaint_id and c.dept_code='PWDBnR'
and c.server_time between '2018-09-03' and '2018-12-19'
You can solve this issue using window functions. For example, if you want your first columns to be a count of the total rows done by the SELECT statement:
select count(1) over(range between unbounded preceding and unbounded following) as total_row_count
, c.complaint_id,c.server_time,c.completion_date,c.road_id,c.photo,c.dept_code,c.dist_code,c.eng_userid,c.feedback_type,c.status,p.dist_name,p.road_name,p.road_dept,e.display_name,e.mobile from complaints as c INNER JOIN pwd_roads as p ON p.road_id=c.road_id INNER JOIN enc_details as e ON CAST(e.enc_code as INTEGER) = p.enccode where c.complaint_id=c.parent_complaint_id and c.dept_code='PWDBnR' and c.server_time between '2018-09-03' and '2018-12-19'
Note that the window function is evaluated before the LIMIT clause if one is used, so if you were to add LIMIT 100 to the query it might give a row count greater than 100 even though a max of 100 rows would be returned.
Easiest but not very elegant way to do this is:
select count(*)
from
(
select c.complaint_id,c.server_time,c.completion_date,c.road_id,c.photo,c.dept_code,c.dist_code,c.eng_userid,c.feedback_type,c.status,p.dist_name,p.road_name,p.road_dept,e.display_name,e.mobile from complaints as c INNER JOIN pwd_roads as p ON p.road_id=c.road_id INNER JOIN enc_details as e ON CAST(e.enc_code as INTEGER) = p.enccode where c.complaint_id=c.parent_complaint_id and c.dept_code='PWDBnR' and c.server_time between '2018-09-03' and '2018-12-19'
)
Related
In my query there is a value that will not match in the demand category table. Therefore, since one value does not match in the output of my query, other matching values do not appear.
I want to do;
How can I list other matching values even if there is an unmatched value in the query?
process Table
fk_unit_id fk_unit_position fk_demand_category
1 2 1
unit table
unit_id
1
unit_position table
unit_position
2
demand_category table
demand_category
1
Query:
SELECT unit_name,unit_position_name,demand_category_name From process
INNER JOIN unit ON process.fk_unit_id = unit_id and unit_id =1
INNER JOIN unit_position ON process.fk_unit_position_id = unit_position_id and unit_position_id = 2
INNER JOIN demand_category ON process.fk_demand_category_id = demand_category_id and demand_category_id =0 ;
Switch INNER JOIN on demand_category with LEFT JOIN
LEFT JOIN gets all records from the LEFT linked and the related record from the right table ,but if you have selected some columns from the RIGHT table, if there is no related records, these columns will contain NULL.
SELECT unit_name,unit_position_name,demand_category_name From process
INNER JOIN unit ON process.fk_unit_id = unit_id and unit_id =1
INNER JOIN unit_position ON process.fk_unit_position_id = unit_position_id and unit_position_id = 2
LEFT JOIN demand_category ON process.fk_demand_category_id = demand_category_id and demand_category_id =0 ;
You can use outer join to have the columns that don't match, just the corresponding values in other table will be padded with null. Other way is to use IN operator, but slower query performance.
I am trying to join 2 tables like so:
left join (
select t1.createdate, min(f1.createdate) as mindt, f1.status_aft
from new_table t1
left join new_folder f1 on t1.veh_id = f1.veh_id
where f1.createdate > t1.createdate
group by t1.createdate
) h3
on t1.createdate = h3.createdate
and f1.createdate = h3.mindt
But I am getting an error:
ERROR: column "f1.status_aft" must appear in the GROUP BY clause or be used in an aggregate function
This makes sense because I do not group it, my goal is just to take the value that is in that current row when f1.createdate is min.
For example:
A B C
one 10 a
one 15 b
two 20 c
two 25 d
Becomes
A B C
one 10 a
two 20 c
Because a and c was the values when column B were the lowest after grouping it by column A.
I've seen this answer but I still can't apply it to my scenario.
How can I achieve the desired result?
my goal is just to take the value that is in that current row when f1.createdate is min.
If you want just one row, you can order by and limit:
left join (
select t1.t1.createdate, f1.createdate as mindt, f1.status_aft
from new_table t1
left join new_folder f1 on t1.veh_id = f1.veh_id
where f1.createdate > t1.createdate
order by t1.createdate limit 1
) h3
I have created the following query:
select t.id, t.row_id, t.content, t.location, t.retweet_count, t.favorite_count, t.happened_at,
a.id, a.screen_name, a.name, a.description, a.followers_count, a.friends_count, a.statuses_count,
c.id, c.code, c.name,
t.parent_id
from tweets t
join accounts a on a.id = t.author_id
left outer join countries c on c.id = t.country_id
where t.row_id > %s
-- order by t.row_id
limit 100
Where %s is a number that starts at 0 and is incremented by 100 after each such query is conducted. I want to fetch all records from the database using this method, where I just increase the %s in the where condition. I found this approach on https://ivopereira.net/efficient-pagination-dont-use-offset-limit. I also included a column in my table which is corresponding to row number (I named it row_id). Now the problem is when I run this query the first time, it returns rows which have an row_id of 3 million. I would like the cursor (not sure if my terminology is correct) to start from rows with row_id 1 through 100 and so on. The table contains 7 million rows. Am I missing something obvious with which I could achieve my goal?
I have two tables: contracts and contract_descriptions.
On contract_descriptions there is a column named contract_id which is equal on contracts table records.
I am trying to join the latest record on contract_descriptions:
SELECT *
FROM contracts c
LEFT JOIN contract_descriptions d ON d.contract_id = c.contract_id
AND d.date_description =
(SELECT MAX(date_description)
FROM contract_descriptions t
WHERE t.contract_id = c.contract_id)
It works, but is it the performant way to do it? Is there a way to avoid the second SELECT?
You could also alternatively use DISTINCT ON:
SELECT * FROM contracts c LEFT JOIN (
SELECT DISTINCT ON (cd.contract_id) cd.* FROM contract_descriptions cd
ORDER BY cd.contract_id, cd.date_description DESC
) d ON d.contract_id = c.contract_id
DISTINCT ON selects only one row per contract_id while the sort clause cd.date_description DESC ensures that it is always the last description.
Performance depends on many values (for example, table size). In any case, you should compare both approaches with EXPLAIN.
Your query looks okay to me. One typical way to join only n rows by some order from the other table is a lateral join:
SELECT *
FROM contracts c
CROSS JOIN LATERAL
(
SELECT *
FROM contract_descriptions cd
WHERE cd.contract_id = c.contract_id
ORDER BY cd.date_description DESC
FETCH FIRST 1 ROW ONLY
) cdlast;
In a table I have records with id's 2,4,5,8. How can I receive a list with values 1,3,6,7. I have tried in this way
SELECT t1.id + 1
FROM table t1
WHERE NOT EXISTS (
SELECT *
FROM table t2
WHERE t2.id = t1.id + 1
)
but it's not working correctly. It doesn't bring all available positions.
Is it possible without another table?
You can get all the missing ID's from a recursive CTE, like this:
with recursive numbers as (
select 1 number
from rdb$database
union all
select number+1
from rdb$database
join numbers on numbers.number < 1024
)
select n.number
from numbers n
where not exists (select 1
from table t
where t.id = n.number)
the number < 1024 condition in my example limit the query to the max 1024 recursion depth. After that, the query will end with an error. If you need more than 1024 consecutive ID's you have either run the query multiple times adjusting the interval of numbers generated or think in a different query that produces consecutive numbers without reaching that level of recursion, which is not too difficult to write.