I have 1 table that contains the main rows and i want all of these rows. Then there are 2 tables that may not have a matching row, but i still want the row from the main table if there is no matching row for these tables.
This query works, but if there is not a row in all 3 tables nothing gets returned. Im using mysql with php.
SELECT PS_Info.* , PS_Guides.Guide, PS_User.UserID FROM PS_Info
JOIN PS_Guides ON PS_Info.ID = PS_Guides.InfoID
JOIN PS_User ON PS_Info.ID = PS_User.InfoID
WHERE PS_Info.GameID = :ID AND PS_User.UserID = :UserID
I am trying to display a list which is in PS_Info. Then i want to hide some of these items if the user has them set to hidden (PS_User = UserID, InfoID). If there is nothing in PS_User then they have not set this item to be hidden so i want to display it. PS_Guides contains extra info about each of the items in the list. Not all items contain extra info so if there is no row in this table then i dont display it.
SELECT PS_Info.* , PS_Guides.Guide, PS_User.UserID FROM PS_Info
left JOIN PS_Guides ON PS_Info.ID = PS_Guides.InfoID //use left join
left JOIN PS_User ON PS_Info.ID = PS_User.InfoID //use left join
WHERE PS_Info.GameID = :ID AND PS_User.UserID = :UserID
You are looking for 'left join'.
SELECT PS_Info.* , PS_Guides.Guide, PS_User.UserID FROM PS_Info
LEFT JOIN PS_Guides ON PS_Info.ID = PS_Guides.InfoID
LEFT JOIN PS_User ON PS_Info.ID = PS_User.InfoID
WHERE PS_Info.GameID = :ID AND PS_User.UserID = :UserID
Related
I am having issues with getting this double left join to get the listingspecificsListPrice, but that info exists in the table, cant figure out why it would not include it. This is my sql.
SELECT mls_subject_property.*, mls_images.imagePath, mls_forms_listing_specifics.listingspecificsListPrice
FROM mls_subject_property
LEFT JOIN mls_images ON mls_subject_property.mls_listingID = mls_images.mls_listingID
LEFT JOIN mls_forms_listing_specifics ON mls_forms_listing_specifics.mls_listingID = mls_subject_property.mls_listingID AND mls_images.imgOrder = 0
WHERE userID = 413
GROUP BY mls_subject_property.mls_listingID
The result comes out like this..
All of the other fields come back, but it doesnt seem to want to bring back those two items.
This is a picture of the other table, to show that the data does in fact exist.
The mls_images.imgOrder = 0 condition should be in the join with mls_images, not mls_forms_listing_specifics.
Don't use GROUP BY if you're not using any aggregation functions. Use SELECT DISTINCT to prevent duplicates.
SELECT DISTINCT mls_subject_property.*, mls_images.imagePath, mls_forms_listing_specifics.listingspecificsListPrice
FROM mls_subject_property
LEFT JOIN mls_images ON mls_subject_property.mls_listingID = mls_images.mls_listingID AND mls_images.imgOrder = 0
LEFT JOIN mls_forms_listing_specifics ON mls_forms_listing_specifics.mls_listingID = mls_subject_property.mls_listingID
WHERE userID = 413
I've got a script where checked in employee's can see the stock inventory from each other, linked with their personal stock location, so each checked in employee can see which items are in stock at different locations. However, I want the main stock (id of 1, which is not attached to an employee) to be showed always, but I can't get the query right because one of the where statements is clearly not correct:
`stock_locations`.`location_id` = 1 AND
`workschedule`.`checkedIn` = 1 AND
Rememeber, the main stock is not linked to an employee, so it doesn't show up at the workschedule table. If I remove the first statement, It clearly shows up all the checked in employee's with their location, but that doesn't give me the main stock. If I remove the second statement, it only shows me the main stock.
How can I solve this issue within SQL? This is btw the full statement:
SELECT
`item_quantities`.`item_id`,
`stock_locations`.`location_name`,
`item_quantities`.`quantity`,
`people`.`first_name`
FROM
`item_quantities`
JOIN `stock_locations` ON `item_quantities`.`location_id` = `stock_locations`.`location_id`
JOIN `items` ON `item_quantities`.`item_id` = `items`.`item_id`
LEFT JOIN `workschedule` ON `workschedule`.`linked_storage` = `stock_locations`.`location_id`
LEFT JOIN `people` ON `workschedule`.`employee_id` = `people`.`person_id`
WHERE
`stock_locations`.`location_id` = 1 AND
`workschedule`.`checkedIn` = 0 AND
`items`.`unit_price` != 0 AND
`items`.`deleted` = 0 AND
`stock_locations`.`deleted` = 0 NULL
Thanks in advance!
Make it an OR statement inside of parens.
(`stock_locations`.`location_id` = 1 OR `workschedule`.`checkedIn` = 1) AND
This will return all records that match either the main stock or the employee.
You need to use the OR operator. Clearly both things can't happen at the same time, so you need to specify each set of acceptable conditions.
SELECT
`item_quantities`.`item_id`,
`stock_locations`.`location_name`,
`item_quantities`.`quantity`,
`people`.`first_name`
FROM
`item_quantities`
JOIN `stock_locations`
ON `item_quantities`.`location_id` = `stock_locations`.`location_id`
JOIN `items`
ON `item_quantities`.`item_id` = `items`.`item_id`
LEFT JOIN `workschedule`
ON `workschedule`.`linked_storage` = `stock_locations`.`location_id`
LEFT JOIN `people`
ON `workschedule`.`employee_id` = `people`.`person_id`
WHERE
`stock_locations`.`location_id` = 1
OR (
AND `workschedule`.`checkedIn` = 1
AND `items`.`unit_price` != 0
AND `items`.`deleted` = 0
AND `stock_locations`.`deleted` = 0
NULL
)
You have LEFT JOIN, but your WHERE clause turns them into inner joins. Fixing that will probably fix your problem:
SELECT . . .
FROM item_quantities iq JOIN
stock_locations sl
ON iq.`location_id` = sl.`location_id` JOIN
items i
ON iq.`item_id` = i.`item_id` LEFT JOIN
workschedule ws
ON ws.`linked_storage` = sl.`location_id` AND
ws.`checkedIn` = 0 LEFT JOIN
--------^
people p
ON ws.`employee_id` = p.`person_id`
WHERE sl.`location_id` = 1 AND
i.`unit_price` != 0 AND
i.`deleted` = 0 AND
sl.`deleted` = 0
So my database is composed of 5 tables with different columns for each one. The only column that keeps them all identified is the id. I'm trying to get the data for a specific user, but I only seem to get all users of the database instead.
This is what I have tried:
SELECT
ControlAccess.UserName,
ControlAccess.Pass,
Users.First_Name,
Users.Last_Name,
UserInfo.Age,
UserInfo.Country,
UserInfo.Address,
UserInfo.ZipCode,
Sessions.Matrix1,
Sessions.Matrix2,
Sessions.Result,
Operations.Operation,
FilePath.LocationFiles
FROM
MatrixUsers.UserInfo
INNER JOIN
MatrixUsers.Users
ON
UserInfo.idUserInfo = Users.idUsers = 1
INNER JOIN
MatrixUsers.ControlAccess
ON
ControlAccess.idControlAccess = UserInfo.idUserInfo = 1
INNER JOIN
MatrixUsers.Sessions
ON
Sessions.idSessions = ControlAccess.idControlAccess = 1
INNER JOIN
MatrixUsers.FilePath
ON
FilePath.idFilePath = Sessions.idSessions = 1
INNER JOIN
MatrixUsers.Operations
ON
Operations.idOperations = FilePath.idFilePath = 1;
I tried putting 1 at the end of each id to see if they matched, but I still get all the users.
I'm new to SQL and I'm only familiar with matching rows, but not choosing specific one.
Here are the columns of each table:
ControlAccess: {idControlAccess, UserName, Pass}
Sessions: {idSessions, Matrix1, Matrix2, Result}
FilePath: {idFilePath, LocationFiles}
Operations: {idOperation, Operation}
UserInfo: {idUserInfo, Age, Country, Address, ZipCode, Phone}
Use WHERE when you want specific user. for example, select user_id from table where user_id=the_specific_user_id . Follow this basic to built you complicate statement.
Just user where after all the joins
WHERE ANY_COLUMN_REFER_TO_USER_ID = YOUR_NEEDED_ID
so your full query would be like :
SELECT
ControlAccess.UserName,
ControlAccess.Pass,
Users.First_Name,
Users.Last_Name,
UserInfo.Age,
UserInfo.Country,
UserInfo.Address,
UserInfo.ZipCode,
Sessions.Matrix1,
Sessions.Matrix2,
Sessions.Result,
Operations.Operation,
FilePath.LocationFiles
FROM MatrixUsers.UserInfo
INNER JOIN MatrixUsers.Users
ON UserInfo.idUserInfo = Users.idUsers
INNER JOIN MatrixUsers.ControlAccess
ON ControlAccess.idControlAccess = UserInfo.idUserInfo
INNER JOIN MatrixUsers.Sessions
ON Sessions.idSessions = ControlAccess.idControlAccess
INNER JOIN MatrixUsers.FilePath
ON FilePath.idFilePath = Sessions.idSessions
INNER JOIN MatrixUsers.Operations
ON Operations.idOperations = FilePath.idFilePath
WHERE UserInfo.idUserInfo = 1
I am having 4 tables.
I want to update all table for that i am using joins.
Query is working only if all tables have values. If any one table does not have record for that than it is not updating other tables
MY query is
update post_message_users
LEFT JOIN post_messages
ON post_message_users.messageid = post_messages.messageid
LEFT JOIN comments
ON post_message_users.messageid = comments.comment_on
LEFT JOIN likes
ON post_message_users.messageid =likes.element_id
SET post_message_users.status='deleted',
post_message_users.deleted_time=NOW(),
post_messages.status = 'deleted' ,
post_messages.delete_time = now(),
comments.status ='deleted',
likes.status='deleted',
likes.delete_time=now()
WHERE
comments.element_type ='Message'
AND
likes.element_type ='Message'
and post_message_users.messageid = 33
and post_message_users.received_by= 3
Please see what change should I make so that i work properly.
Your where clause is undoing the left outer join, turning it into an inner join. To fix this, move the conditions into the on clause:
update post_message_users
LEFT JOIN post_messages
ON post_message_users.messageid = post_messages.messageid
LEFT JOIN comments
ON post_message_users.messageid = comments.comment_on and
comments.element_type = 'Message'
LEFT JOIN likes
ON post_message_users.messageid = likes.element_id and
likes.element_type = 'Message'
SET post_message_users.status='deleted',
post_message_users.deleted_time=NOW(),
post_messages.status = 'deleted' ,
post_messages.delete_time = now(),
comments.status ='deleted',
likes.status='deleted',
likes.delete_time=now()
WHERE post_message_users.messageid = 33 and post_message_users.received_by= 3;
I have a situation where a property table holds an address id (from the g_addresses table) and an applicant table also holds an address id from the g_addresses.
I'd like to left join these together but select all the fields in the table.
I know of using 'as' to make an alias for fields, but is there any way to produce an alias for a whole table?
SELECT *
FROM (`reference`)
LEFT JOIN `applicants` ON `applicants`.`id` = `reference`.`applicant_id`
LEFT JOIN `g_people` applicant_person ON `applicant_person`.`id` = `applicants`.`person_id`
LEFT JOIN `g_addresses` applicant_address ON `applicant_address`.`id` = `applicants`.`address_id`
LEFT JOIN `properties` ON `properties`.`id` = `reference`.`property_id`
LEFT JOIN `g_addresses` property_address ON `property_address`.`id` = `properties`.`address_id`
WHERE `reference`.`id` = 4
This produces a result containing only one address row and not both,
The row that is returned is the row from the final join and not the one previously, indicating it is overwriting when it is returned.
I don't think you should use masked references, like * or `reference`.*, in your case, because you may end up with a row set containing identical column names (id, address_id).
If you want to pull all the columns from the joined tables, you should probably specify them individually in the SELECT clause and assign a unique alias to every one of them:
SELECT
ref.`id` AS ref_id,
ref.`…` AS …,
…
app.`id` AS app_id,
…
FROM `reference` AS ref
LEFT JOIN `applicants` AS app ON app.`id` = ref.`applicant_id`
LEFT JOIN `g_people` AS ape ON ape.`id` = app.`person_id`
LEFT JOIN `g_addresses` AS apa ON apa.`id` = app.`address_id`
LEFT JOIN `properties` AS pro ON pro.`id` = ref.`property_id`
LEFT JOIN `g_addresses` AS pra ON pra.`id` = pro.`address_id`
WHERE ref.`id` = 4
Be more specific about columns you select
SELECT
applicant_address.*,
property_address.*,
applicants.*,
applicant_person.*,
properties.*
FROM (`reference`)
LEFT JOIN `applicants` ON `applicants`.`id` = `reference`.`applicant_id`
LEFT JOIN `g_people` applicant_person ON `applicant_person`.`id` = `applicants`.`person_id`
LEFT JOIN `g_addresses` applicant_address ON `applicant_address`.`id` = `applicants`.`address_id`
LEFT JOIN `properties` ON `properties`.`id` = `reference`.`property_id`
LEFT JOIN `g_addresses` property_address ON `property_address`.`id` = `properties`.`address_id`
WHERE `reference`.`id` = 4