I've (on reflection ridiculously) stored our 'punters' in 2 tables depending on whether they registered or paid through the express checkout form.
My SQL looks like this:
SELECT
DISTINCT(sale_id), sale_punter_type, sale_comment, sale_refund, sale_timestamp,
punter_surname, punter_firstname,
punter_checkout_surname, punter_checkout_firstname,
punter_compo_surname, punter_compo_firstname,
sale_random, sale_scanned, sale_id
FROM
sale
LEFT JOIN
punter ON punter_id = sale_punter_no
LEFT JOIN
punter_checkout ON punter_checkout_id = sale_punter_no
LEFT JOIN
punter_compo ON punter_compo_id = sale_punter_no
WHERE
sale_event_no = :id
ORDER BY
punter_surname, punter_firstname,
punter_checkout_surname, punter_checkout_firstname
It returns results BUT lists the registered users alphabetically first, then the checkout punters alphabetically.
My question is there a way to get all of the users (registered or checkout) all together sorted alphabetically in 1 sorted list instead of 2 joined sorted lists.
I thought maybe I could use something like punter_checkout_surname AS punter_surname but that didn't work.
Any thoughts? I know now that I shouldn't have used 2 separate tables but but I'm stuck with it now.
Thank you.
I think you just want to use coalesce().
ORDER BY COALESCE(punter_surname, punter_checkout_surname)
COALESCE(punter_firstname, punter_checkout_firstname)
Other comments:
I doubt that DISTINCT is necessary. Why would this generate multiple rows for a single sale_id?
When a query has multiple tables, qualify all the column names (that is, include table aliases so you and others know where the table comes from).
Your data has three sets of names. That seems overkill.
You might want to put the COALESCE() in the SELECT so you don't have quite so many names generated by the query.
Here's my answer:
ORDER BY
COALESCE( UCASE( punter_surname) , UCASE( punter_checkout_surname ), UCASE( punter_compo_surname ) ) ,
COALESCE( UCASE( punter_firstname ) , UCASE( punter_checkout_firstname ), UCASE( punter_compo_firstname) )
Related
We have two tables one is properties and another one is property meta when we are getting data from one table "properties" , query only take less then one second in execution but when we are use join to get the data using bellow query from both tables its taking more then 5 second to fetch the data although we have only 12000 record in the tables , i think there is an issue in the sql query any help or suggestion will be appreciated.
SELECT
u.id,
u.property_title,
u.description,
u.city,
u.area,
u.address,
u.slug,
u.latitude,
u.longitude,
u.sync_time,
u.add_date,
u.is_featured,
u.pre_construction,
u.move_in_date,
u.property_status,
u.sale_price,
u.mls_number,
u.bedrooms,
u.bathrooms,
u.kitchens,
u.sub_area,
u.property_type,
u.main_image,
u.area_size as land_area,
pm7.meta_value as company_name,
pm8.meta_value as virtual_tour,
u.year_built,
u.garages
FROM
tbl_properties u
LEFT JOIN tbl_property_meta pm7
ON u.id = pm7.property_id
LEFT JOIN tbl_property_meta pm8
ON u.id = pm8.property_id
WHERE
u.status = 1
AND (pm7.meta_key = 'company_name')
AND (pm8.meta_key = 'virtual_tour')
AND (
(
( u.city = 'Delta'
OR u.post_code LIKE '%Delta%'
OR u.sub_area LIKE '%Delta%'
OR u.state LIKE '%Delta%')
AND country = 'Canada'
)
OR (
( u.city = 'Metro Vancouver Regional District'
OR u.post_code LIKE '%Metro Vancouver Regional District%'
OR u.sub_area LIKE '%Metro Vancouver Regional District%'
OR u.state LIKE '%Metro Vancouver Regional District%' )
AND country = 'Canada'
)
)
AND
u.pre_construction ='0'
GROUP BY
u.id
ORDER BY
u.is_featured DESC,
u.add_date DESC
Try adding this compound index:
ALTER TABLE tbl_property_meta ADD INDEX id_key (property_id, meta_key);
If it doesn't help make things faster, try this one.
ALTER TABLE tbl_property_meta ADD INDEX key_id (meta_key, property_id);
And, you should know that column LIKE '%somevalue' (with a leading %) is a notorious performance antipattern, resistant to optimization via indexes. (There's a way to create indexes for that shape of filter in PostgreSQL, but not in MariaDB / MySQL.)
Add another column with the meta stuff; throw city, post_code, sub_area, and state and probably some other things into it. Then build a FULLTEXT index on that column. Then use MATCH(..) AGAINST("Delta Metro Vancouver Regional District") in the WHERE clause _instead of the LEFT JOINs (which are actually INNER JOINs) and the really messy part of the WHERE clause.
Also, the GROUP BY is probably unnecessary, thereby eliminating extra sort on the intermediate set of rows.
I have a list of categories that are saved in a string. One is on an article table the other on an ad table. I need the script to return all rows that have a combination of any of these categories between the two tables.
Category string on both tables:
Civic,Community,Sports,Business
And my MySQL script
SELECT `Ad_ID`, `Ad_URL`, `Ad_Image`, `Ad_Type`, `Ad_Cities`, `Ad_Categories`
FROM `Ad_TABLE`
INNER JOIN `Article_TABLE` ON `Article_TABLE`.`Article_Cat` = `Ad_TABLE`.`Ad_Cat`
WHERE Article_TABLE.Article_Cat LIKE '%Civic%'
OR Article_TABLE.Article_Cat LIKE '%Community%'
OR Article_TABLE.Article_Cat LIKE '%Sports%'
OR Article_TABLE.Article_Cat LIKE '%Business%'
AND Ad_TABLE.Ad_Cat LIKE '%Civic%'
OR Ad_TABLE.Ad_Cat LIKE '%Community%'
OR Ad_TABLE.Ad_Cat LIKE '%Sports%'
OR Ad_TABLE.Ad_Cat LIKE '%Business%'
The script only returns records that are only in one of these categories, but there are records that are in multiple categories and I need it to return those as well.
How can I get it to where it finds all matching categories between the two tables?
I suspect you need to add parenthesis to the WHERE clause:
SELECT `Ad_ID`, `Ad_URL`, `Ad_Image`, `Ad_Type`, `Ad_Cities`, `Ad_Categories`
FROM `Ad_DB`
INNER JOIN `Article_DB` ON `Article_DB`.`Article_Cat` = `Ad_DB`.`Ad_Cat`
WHERE (Article_DB.Article_Cat LIKE '%Civic%'
OR Article_DB.Article_Cat LIKE '%Community%'
OR Article_DB.Article_Cat LIKE '%Sports%'
OR Article_DB.Article_Cat LIKE '%Business%')
AND (Ad.DB_Cat LIKE '%Civic%'
OR Ad.DB_Cat LIKE '%Community%'
OR Ad.DB_Cat LIKE '%Sports%'
OR Ad.DB_Cat LIKE '%Business%')
I'm not sure exactly how your tables are structured, but this query will return rows where Article_DB.Article_Cat AND Ad.DB_Cat contain one of your categories. You likely want to rethink the way you store data in these tables so that you're not duplicating data.
Here's a guess. This is just a guess, based on a possible interpretation of the nebulous specification.
To "match" rows that have one or more of these four categories in common
Civic,Community,Sports,Business
We could use a query with join predicates like this:
SELECT ...
FROM `Ad_DB` d
JOIN `Article_DB` r
ON ( FIND_IN_SET('Civic' ,d.ad_categories)
AND FIND_IN_SET('Civic' ,r.article_cat )
)
OR ( FIND_IN_SET('Community' ,d.ad_categories)
AND FIND_IN_SET('Community' ,r.article_cat )
)
OR ( FIND_IN_SET('Sports' ,d.ad_categories)
AND FIND_IN_SET('Sports' ,r.article_cat )
)
OR ( FIND_IN_SET('Business' ,d.ad_categories)
AND FIND_IN_SET('Business' ,r.article_cat )
)
ORDER BY ...
NOTE: I understand that we get what we get, and sometimes we get handed a database that stores comma separated lists.
Storing comma separated lists in a column is a SQL Antipattern. For anyone that has an interest as to why it's an antipattern, I recommend Chapter 2 of Bill Karwin's excellent book
https://www.amazon.com/SQL-Antipatterns-Programming-Pragmatic-Programmers/dp/1934356557
I need to write query that joins several tables and I need distinct value from one table based on max count().
These are my tables names and columns:
bands:
db|name|
releases_artists:
release_db|band_db
releases_styles
release_db|style
Relations between tables are (needed for JOINs):
releases_artists.band_db = bands.db
releases_styles.release_db = releases_artists.release_db
And now the query that I need to write:
SELECT b.name, most_common_style
LEFT JOIN releases_artists ra ON ra.band_db = b.db
and here I need to find the most common style from all band releases
JOIN(
SELECT DISTINCT style WHERE releases_styles.release_db = ra.release_db ORDER BY COUNT() DESC LIMIT 1
)
FROM bands b
WHERE b.name LIKE 'something'
This is just a non working example of what I want to accomplish. It would be great if someone could help me build this query.
Thanks in advance.
EDIT 1
Each artist from table bands can have multiple records from releases_artists table based on band_db and each release can have multiple styles from releases_styles based on release_db
So if I search for b.name LIKE '%ray%' it returns something similar to:
`bands`:
o7te|Ray Wilson
9i84|Ray Parkey Jr.
`releases_artists` for Ray Wilson:
tv5c|o7te (for example album `Change`)
78wz|o7te (`The Next Best Thing`)
nz7c|o7te (`Propaganda Man`)
`releases_styles`
tv5c|Pop
tv5c|Rock
tv5c|Alternative Pop/Rock
----
78wz|Rock
78wz|Pop
78wz|Classic Rock
I need style name that repeats mostly from all artist releases as this artist main style.
Ok, this is a bit of a hack. But the only alternatives I could think of involve heaps of nested subqueries. So here goes:
SELECT name
, SUBSTRING_INDEX(GROUP_CONCAT(style ORDER BY release_count DESC SEPARATOR '|'), '|', 1) AS most_common_style
FROM (
SELECT b.db
, b.name
, rs.style
, COUNT(*) AS release_count
FROM bands b
JOIN releases_artists ra ON ra.band_db = b.db
JOIN releases_styles rs ON rs.release_db = ra.release_db
GROUP BY b.db, rs.style
) s
GROUP BY db;
This small SQL error is bugging me. It doesn't seem to be a problem with the query, just the scope(?), examples work best:
SELECT ocp.*, oc.*, GROUP_CONCAT( u.username SEPARATOR ', ') AS `memjoined`
FROM gangs_ocs_process ocp, gangs_ocs oc
LEFT JOIN users u ON u.userid IN ( ocp.membersin )
WHERE ocp.ocid =1 AND ocp.gangid =1 AND oc.oc_name = ocp.crimename
GROUP BY ocp.ocid
LIMIT 0 , 30
Theres a column (gangs_ocs_process.membersin) which has a list of IDs that have joined (ie 1,2,5). I'm trying to get the usernames for each of these IDs (from the users table) in one go.
The problem is LEFT JOIN users u ON u.userid IN ( ocp.membersin )
If I substitue 1,2,4 in for ocp.membersin (putting the literal list instead of column name), it works ok. It returns a column that has the usernames (image). However, if I leave in the ocp.membersin, I get this error:
#1054 - Unknown column 'ocp.membersin' in 'on clause'
This is the first time I've even used IN in left joins so I'm a bit lost.
Any help would be great :)
I don't think that "IN" will work for this syntax. MySQL expects IN to be something akin to a dataset, not a delimited string. I think you need to find a way to take membersin, expand it into a dataset MySQL can work with (maybe a temporary table), and join on that.
If you have delimited strings in your table, you have a design problem in your database. Add a new table to hold these values.
Are you sure 'membersin' is in the 'gangs_ocs_process' table, and not the 'gangs_ocs' table?
The reason you can't get it to work is because first you need to get your database NORMALIZED. You should NEVER, EVER have a list of ID's in a single column.
After taking another look, I think your problem is trying to aggregate at the wrong point as well as the IN syntax and that you should aggregate in a subquery restricted by the contents of the IN. I don't know enough about your schema to make this out of the box correct, but you want something like this. SomeKeyfield should relate back to gangs_ocs_process
SELECT ocp.*, oc.*, u.Memjoined
FROM gangs_ocs_process ocp, gangs_ocs oc
LEFT JOIN (Select SomeKeyField, GROUP_CONCAT( u.username SEPARATOR ', ') as memjoined
from users where userid in
(select membersin from gangs_ocs_process
where [whatever conditions] )
Group By SomeKeyField) u on ocp.SomeKeyField = u.SomeKeyField
WHERE ocp.ocid =1 AND ocp.gangid =1 AND oc.oc_name = ocp.crimename
GROUP BY ocp.ocid
LIMIT 0 , 30
This is a bad way to keep membership.
But if you still need to live with it, you may try REGEXP matching to test for membership:
SELECT ocp.*, oc.*, GROUP_CONCAT( u.username SEPARATOR ', ') AS `memjoined`
FROM gangs_ocs_process ocp
LEFT JOIN users u ON (ocp.membersin RLIKE CONCAT('(^|,)[[:blank:]]?', userid, '[[:blank:]]?($|,)'))
JOIN gangs_ocs oc ON (ocp.ocid = 1 AND ocp.gangid = 1 AND oc.oc_name = ocp.crimename)
GROUP BY ocp.ocid
LIMIT 0 , 30
I'm in over my head with a big mysql query (mysql 5.0), and i'm hoping somebody here can help.
Earlier I asked how to get distinct values from a joined query
mysql count only for distinct values in joined query
The response I got worked (using a subquery with join as)
select *
from media m
inner join
( select uid
from users_tbl
limit 0,30) map
on map.uid = m.uid
inner join users_tbl u
on u.uid = m.uid
unfortunately, my query has grown more unruly, and though I have it running, joining into a derived table is taking too long because there is no indexes available to the derived query.
my query now looks like this
SELECT mdate.bid, mdate.fid, mdate.date, mdate.time, mdate.title, mdate.name,
mdate.address, mdate.rank, mdate.city, mdate.state, mdate.lat, mdate.`long`,
ext.link,
ext.source, ext.pre, meta, mdate.img
FROM ext
RIGHT OUTER JOIN (
SELECT media.bid,
media.date, media.time, media.title, users.name, users.img, users.rank, media.address,
media.city, media.state, media.lat, media.`long`,
GROUP_CONCAT(tags.tagname SEPARATOR ' | ') AS meta
FROM media
JOIN users ON media.bid = users.bid
LEFT JOIN tags ON users.bid=tags.bid
WHERE `long` BETWEEN -122.52224684058 AND -121.79760915942
AND lat BETWEEN 37.07500915942 AND 37.79964684058
AND date = '2009-02-23'
GROUP BY media.bid, media.date
ORDER BY media.date, users.rank DESC
LIMIT 0, 30
) mdate ON (mdate.bid = ext.bid AND mdate.date = ext.date)
phew!
SO, as you can see, if I understand my problem correctly, i have two derivative tables without indexes (and i don't deny that I may have screwed up the Join statements somehow, but I kept messing with different types, is this ended up giving me the result I wanted).
What's the best way to create a query similar to this which will allow me to take advantage of the indexes?
Dare I say, I actually have one more table to add into the mix at a later date.
Currently, my query is taking .8 seconds to complete, but I'm sure if I could take advantage of the indexes, this could be significantly faster.
First, check for indices on ext(bid, date), users(bid) and tags(bid), you should really have them.
It seems, though, that it's LONG and LAT that cause you most problems. You should try keeping your LONG and LAT as a (coordinate POINT), create a SPATIAL INDEX on this column and query like that:
WHERE MBRContains(#MySquare, coordinate)
If you can't change your schema for some reason, you can try creating additional indices that include date as a first field:
CREATE INDEX ix_date_long ON media (date, `long`)
CREATE INDEX ix_date_lat ON media (date, lat)
These indices will be more efficient for you query, as you use exact search on date combined with a ranged search on axes.
Starting fresh:
Question - why are you grouping by both media.bid and media.date? Can a bid have records for more than one date?
Here's a simpler version to try:
SELECT
mdate.bid,
mdate.fid,
mdate.date,
mdate.time,
mdate.title,
mdate.name,
mdate.address,
mdate.rank,
mdate.city,
mdate.state,
mdate.lat,
mdate.`long`,
ext.link,
ext.source,
ext.pre,
meta,
mdate.img,
( SELECT GROUP_CONCAT(tags.tagname SEPARATOR ' | ')
FROM tags
WHERE ext.bid = tags.bid
ORDER BY tags.bid GROUP BY tags.bid
) AS meta
FROM
ext
LEFT JOIN
media ON ext.bid = media.bid AND ext.date = media.date
JOIN
users ON ext.bid = users.bid
WHERE
`long` BETWEEN -122.52224684058 AND -121.79760915942
AND lat BETWEEN 37.07500915942 AND 37.79964684058
AND ext.date = '2009-02-23'
AND users.userid IN
(
SELECT userid FROM users ORDER BY rank DESC LIMIT 30
)
ORDER BY
media.date,
users.rank DESC
LIMIT 0, 30
You might want to compare your perforamnces against using a temp table for each selection, and joining those tables together.
create table #whatever
create table #whatever2
insert into #whatever select...
insert into #whatever2 select...
select from #whatever join #whatever 2
....
drop table #whatever
drop table #whatever2
If your system has enough memory to hold full tables this might work out much faster. It depends on how big your database is.