This table has the values of profileId which is the user and eventId which is an event that the user can join. I am trying to implement a way for a user to not be able to attend the same event. I tried doing ON CONFLICT..
insert into "attendees"("profileId","eventId")
values($1,$2)
on conflict ("profileId", "eventId") do nothing
returning *;
...but the syntax is probably wrong of what goes inside the parenthesis after on conflict.
Just to make things more clear, profileId=151 eventId=186 and profileId=151 eventId=187 is acceptable, but profileId=151 eventId =186 and profileId=151 and eventId=186 is not because that means the same user is attending the same event.
first you need to make a unique index on (profileid , eventid) keys
CREATE UNIQUE INDEX UQ_attendees on attendees (profileId,eventId)
you can change your query to this :
insert into attendees (profileId,eventId)
values($1,$2)
on conflict (profileId,eventId) do nothing;
Have you an unique index or pk over the conflicted fields? I tested it:
create table frank(id serial, texto varchar(50), fecha timestamp, CONSTRAINT pk_frank primary key(texto) );
insert into frank(texto, fecha) values('hola', now()), ('chau', now());
INSERT 0 2
=# select * from frank
-# ;
id | texto | fecha
----+-------+----------------------------
1 | hola | 2021-03-29 14:23:12.829833
2 | chau | 2021-03-29 14:23:12.829833
(2 rows)
insert into frank(texto, fecha) values('hola', now()), ('chau', now()), ('que tal', now()) on conflict do nothing ;
INSERT 0 1
=# select * from frank
;
id | texto | fecha
----+---------+----------------------------
1 | hola | 2021-03-29 14:23:12.829833
2 | chau | 2021-03-29 14:23:12.829833
6 | que tal | 2021-03-29 14:24:04.637864
(3 rows)
Related
Table1
Columns PK_Table1 Name | DoYouGoToSchool |DoYouhaveACar |DoYouWorkFullTime | DoYouWorkPartTime | Score
1 joe Yes Yes No Yes
2 amy No Yes Yes No
Table2
Columns Pk_Table2 |Question | Answer(Bit Column) |Value
1 DoYouGoToSchool True 3
2 DoYouhaveACar True 2
3 DoYouWorkFullTime True 4
4 DoYouWorkPartTime True 2
Based on the information from Table2 What i need to do is UPDATE Table1 ColumnName Score by summing up the Value from Table2 with the information he has provided.
for example i expect the Score column in table1 to be 7 for record 1
and 5 for record 2
Here is a query to play with
IF OBJECT_ID('tempdb..#Table2') IS NOT NULL DROP TABLE #Table2
GO
IF OBJECT_ID('tempdb..#Table1') IS NOT NULL DROP TABLE #Table1
GO
create table #Table1
(
PK_Table1 int,
Name Varchar(50),
DoYouGoToSchool Varchar(8),
DoYouhaveACar Varchar(8),
DoYouWorkFullTime Varchar(8),
DoYouWorkPartTime Varchar(8),
Score INT NULL,
)
create table #Table2
(
PK_Table2 int,
Questions Varchar(50),
Answer BIT NOT NULL DEFAULT(0),
VALUE INT NULL
)
INSERT INTO #Table1 (Name,DoYouGoToSchool,DoYouhaveACar,DoYouWorkFullTime,DoYouWorkPartTime)
VALUES ('joe','Yes','Yes','No','Yes'), ('amy','NO','Yes','Yes','No')
INSERT INTO #Table2(Questions,Answer,VALUE)
VALUES ('DoYouGoToSchool','True',3 ),('DoYouhaveACar','True',2 ),('DoYouWorkFullTime','True',4 ),('DoYouWorkPartTime','True',2 )
This is what is missing from answer below that tells you to create new FK contraint to the Table2 --Inserting Data into the table with the new FK Column
insert into #Table2 (FK_Table1, Questions, Answer) select t.PK_Table1, t1.cols, colsval from #Table1 t cross apply (values (PK_Table1,'DoYouGoToSchool', DoYouGoToSchool), (PK_Table1,'DoYouhaveACar', DoYouhaveACar), (PK_Table1,'DoYouWorkFullTime', DoYouWorkFullTime), (PK_Table1,'DoYouWorkPartTime', DoYouWorkPartTime) ) t1 (PK_Table1,cols, colsval);
First create a relation between these two tables and add Primary key of Table1 in Table2 as a foreign key so your Table2 becomes:
Table2 Columns:
FK_Table1 |Pk_Table2 |Question | Answer(Bit Column) |Value
1 1 DoYouGoToSchool True 3
1 2 DoYouhaveACar True 2
1 3 DoYouWorkFullTime True 4
1 4 DoYouWorkPartTime True 2
You can add in table by using this Query:
ALTER TABLE Table2
ADD FK_Table1 INTEGER,
ADD CONSTRAINT FOREIGN KEY(FK_Table1) REFERENCES Table1(PK_Table1)
means that it is only for that person whose PK_Table1 = 1
Then you can extract his score from this query:
SELECT Sum(Value) FROM Table2 WHERE FK_Table1 = 1;
And then update query:
UPDATE Table1
SET score = (enter here the returned score from above query)
WHERE PK_Table1 = 1;
Or you can do in a single query like this:
UPDATE Table1
SET score = (SELECT Sum(Value) FROM Table2 WHERE FK_Table1 = 1)
WHERE PK_Table1 = 1;
You will need to add another table. This table will be your relational table. It can be called Table1_Table2 with three columns. The first column will be the primary key for the table. The next column will be the primary key of Table1 and the third column will be the primary key for Table 2.
When an instance of Table2 occurs that relates with Table1, insert a record into Table1_Table2 that relates the two tables together with each others primary key. Then a query can be done on the relational table, Table1_Table2 that allows you to sum the relationships.
|Table1_Table2 |
| PK | PK_Table1 | PK_Table2 |
| 1 | 1 | 1 |
| 2 | 1 | 3 |
| 3 | 2 | 1 |
| 4 | 2 | 4 |
As we can see, we can now perform an update on Table1
UPDATE TABLE1 A SET A.SCORE = (Select SUM(B.Value) FROM Table2 B, Table1_Table2 C WHERE C.PK_Table2 = B.PK_Table2 AND C.PK_Table1 = A.PK_Table1);
I'm trying to figure out how to do a multi-row insert as one statement in SQL Server, but where one of the columns is a column computer based on the data as it stands after every insert row.
Let's say I run this simple query and get back 3 records:
SELECT *
FROM event_courses
WHERE event_id = 100
Results:
id | event_id | course_id | course_priority
---+----------+-----------+----------------
10 | 100 | 501 | 1
11 | 100 | 502 | 2
12 | 100 | 503 | 3
Now I want to insert 3 more records into this table, except I need to be able to calculate the priority for each record. The priority should be the count of all courses in this event. But if I run a sub-query, I get the same priority for all new courses:
INSERT INTO event_courses (event_id, course_id, course_priority)
VALUES (100, 500,
(SELECT COUNT (id) + 1 AS cnt_event_courses
FROM event_courses
WHERE event_id = 100)),
(100, 501,
(SELECT COUNT (id) + 1 AS cnt_event_courses
FROM event_courses
WHERE event_id = 1))
Results:
id | event_id | course_id | course_priority
---+----------+-----------+-----------------
10 | 100 | 501 | 1
11 | 100 | 502 | 2
12 | 100 | 503 | 3
13 | 100 | 504 | 4
14 | 100 | 505 | 4
15 | 100 | 506 | 4
Now I know I could easily do this in a loop outside of SQL and just run a bunch of insert statement, but that's not very efficient. There's got to be a way to calculate the priority on the fly during a multi-row insert.
Big thanks to #Sean Lange for the answer. I was able to simplify it even further for my application. Great lead! Learned 2 new syntax tricks today ;)
DECLARE #eventid int = 100
INSERT event_courses
SELECT #eventid AS event_id,
course_id,
course_priority = existingEventCourses.prioritySeed + ROW_NUMBER() OVER(ORDER BY tempid)
FROM (VALUES
(1, 501),
(2, 502),
(3, 503)
) courseInserts (tempid, course_id) -- This basically creates a temp table in memory at run-time
CROSS APPLY (
SELECT COUNT(id) AS prioritySeed
FROM event_courses
WHERE event_id = #eventid
) existingEventCourses
SELECT *
FROM event_courses
WHERE event_id = #eventid
Here is an example of how you might be able to do this. I have no idea where your new rows values are coming from so I just tossed them in a derived table. I doubt your final solution would look like this but it demonstrates how you can leverage ROW_NUMBER for accomplish this type of thing.
declare #EventCourse table
(
id int identity
, event_id int
, course_id int
, course_priority int
)
insert #EventCourse values
(100, 501, 1)
,(100, 502, 2)
,(100, 503, 3)
select *
from #EventCourse
insert #EventCourse
(
event_id
, course_id
, course_priority
)
select x.eventID
, x.coursePriority
, NewPriority = y.MaxPriority + ROW_NUMBER() over(partition by x.eventID order by x.coursePriority)
from
(
values(100, 504)
,(100, 505)
,(100, 506)
)x(eventID, coursePriority)
cross apply
(
select max(course_priority) as MaxPriority
from #EventCourse ec
where ec.event_id = x.eventID
) y
select *
from #EventCourse
Actually I'm noob and stuck on this problem for a week. I will try explaining it.
I have table for USER,
and a table for product
I want to store data of every user for every product. Like if_product_bought, num_of_items, and all.
So only solution I can think of database within database , that is create a copy of products inside user named database and start storing.
If this is possible how or is there any other better solution
Thanks in advance
You actually don't create a database within a database (or a table within a table) when you use PostgreSQL or any other SQL RDBMS.
You use tables, and JOIN them. You normally would have an orders table, together with an items_x_orders table, on top of your users and items.
This is a very simplified scenario:
CREATE TABLE users
(
user_id INTEGER /* SERIAL */ NOT NULL PRIMARY KEY,
user_name text
) ;
CREATE TABLE items
(
item_id INTEGER /* SERIAL */ NOT NULL PRIMARY KEY,
item_description text NOT NULL,
item_unit text NOT NULL,
item_standard_price decimal(10,2) NOT NULL
) ;
CREATE TABLE orders
(
order_id INTEGER /* SERIAL */ NOT NULL PRIMARY KEY,
user_id INTEGER NOT NULL REFERENCES users(user_id),
order_date DATE NOT NULL DEFAULT now(),
other_data TEXT
) ;
CREATE TABLE items_x_orders
(
order_id INTEGER NOT NULL REFERENCES orders(order_id),
item_id INTEGER NOT NULL REFERENCES items(item_id),
-- You're supposed not to have the item more than once in an order
-- This makes the following the "natural key" for this table
PRIMARY KEY (order_id, item_id),
item_quantity DECIMAL(10,2) NOT NULL CHECK(item_quantity <> /* > */ 0),
item_percent_discount DECIMAL(5,2) NOT NULL DEFAULT 0.0,
other_data TEXT
) ;
This is all based in the so-called Relational Model. What you were thinking about is something else called a Hierarchical model, or a document model used in some NoSQL databases (where you store your data as a JSON or XML hierarchical structure).
You would fill those tables with data like:
INSERT INTO users
(user_id, user_name)
VALUES
(1, 'Alice Cooper') ;
INSERT INTO items
(item_id, item_description, item_unit, item_standard_price)
VALUES
(1, 'Oranges', 'kg', 0.75),
(2, 'Cookies', 'box', 1.25),
(3, 'Milk', '1l carton', 0.90) ;
INSERT INTO orders
(order_id, user_id)
VALUES
(100, 1) ;
INSERT INTO items_x_orders
(order_id, item_id, item_quantity, item_percent_discount, other_data)
VALUES
(100, 1, 2.5, 0.00, NULL),
(100, 2, 3.0, 0.00, 'I don''t want Oreo'),
(100, 3, 1.0, 0.05, 'Make it promo milk') ;
And then you would produce queries like the following one, where you JOIN all relevant tables:
SELECT
user_name, item_description, item_quantity, item_unit,
item_standard_price, item_percent_discount,
CAST(item_quantity * (item_standard_price * (1-item_percent_discount/100.0)) AS DECIMAL(10,2)) AS items_price
FROM
items_x_orders
JOIN orders USING (order_id)
JOIN items USING (item_id)
JOIN users USING (user_id) ;
...and get these results:
user_name | item_description | item_quantity | item_unit | item_standard_price | item_percent_discount | items_price
:----------- | :--------------- | ------------: | :-------- | ------------------: | --------------------: | ----------:
Alice Cooper | Oranges | 2.50 | kg | 0.75 | 0.00 | 1.88
Alice Cooper | Cookies | 3.00 | box | 1.25 | 0.00 | 3.75
Alice Cooper | Milk | 1.00 | 1l carton | 0.90 | 5.00 | 0.86
You can get all the code and test at dbfiddle here
I have following data in employee Table A:
ID | emp | City_Type | City
1 | 101 | Z | Tokyo
2 | 101 | Y | New York
City_Type can either be Y or Z. Y being the city this person was born in, Z is the city he/she is living now.
I need to put these together in a table 'B' which look like the folowing:
ID | emp | Current_City | Birth_City
So in the end, Table B must be filled like this:
ID | emp | Current_City | Birth_City
1 | 101 | Tokyo | New York
(in some cases, one of the 2 can be empty/null)
Any suggestions on how to do this? I haven't been able to found much information on this myself.
I did this exercise (using sql-server) with PIVOT TABLE:
select emp, Z 'Current_City' , Y 'Birth_City' from
(
select emp,City_Type, City from TABLE__A
) x
pivot
(
max(City) FOR City_Type in (Z,Y)
) AS PivotTable
below the result achieved, with an example of a NULL value for the field Current_City
emp Current_City Birth_City
101 Tokyo New York
102 NULL London
I omitted ID, it is not clear from the request if and what needs to be added ( minimum, maximum on emp , or a new calculated or due to the INSERT in TABLE__B)
This previous query can be used to insert into TABLE__B
INSERT INTO [TABLE__B]
([emp]
,[Current_City]
,[Birth_City])
...
First create your TableB and populate [Current_City] and [Birth_City] with nulls, but make sure [emp] is there and it has all the employees you intend to modify.
Then run this SQL modified to fit your database / schema / table names / etc:
update TableB
set Current_City = (select City
from TableA
where TableA.City_Type ='Z'
and TableA.emp = TableB.emp),
Birth_City = (select City
from TableA
where TableA.City_Type ='Y'
and TableA.emp = TableB.emp)
One way would be to use the PIVOT transformation.
Consider this datatable :
word wordCount documentId
---------- ------- ---------------
Ball 10 1
School 11 1
Car 4 1
Machine 3 1
House 1 2
Tree 5 2
Ball 4 2
I want to insert these data into two tables with this structure :
Table WordDictionary
(
Id int,
Word nvarchar(50),
DocumentId int
)
Table WordDetails
(
Id int,
WordId int,
WordCount int
)
FOREIGN KEY (WordId) REFERENCES WordDictionary(Id)
But because I have thousands of records in initial table, I have to do this just in one transaction (batch query) for example using bulk insert can help me doing this purpose.
But the question here is how I can separate this data into these two tables WordDictionary and WordDetails.
For more details :
Final result must be like this :
Table WordDictionary:
Id word
---------- -------
1 Ball
2 School
3 Car
4 Machine
5 House
6 Tree
and table WordDetails :
Id wordId WordCount DocumentId
---------- ------- ----------- ------------
1 1 10 1
2 2 11 1
3 3 4 1
4 4 3 1
5 5 1 2
6 6 5 2
7 1 4 2
Notice :
The words in the source can be duplicated so I must check word existence in table WordDictionary before any insert record in these tables and if a word is found in table WordDictionary, the just found Word ID must be inserted into table WordDetails (please see Word Ball)
Finally the 1 M$ problem is: this insertion must be done as fast as possible.
If you're looking to just load the table the first time without any updates to the table over time you could potentially do it this way (I'm assuming you've already created the tables you're loading into):
You can put all of the distinct words from the datatable into the WordDictionary table first:
SELECT DISTINCT word
INTO WordDictionary
FROM datatable;
Then after you populate your WordDictionary you can then use the ID values from it and the rest of the information from datatable to load your WordDetails table:
SELECT WD.Id as wordId, DT.wordCount as WordCount, DT.documentId AS DocumentId
INTO WordDetails
FROM datatable as DT
INNER JOIN WordDictionary AS WD ON WD.word = DT.word
There a little discrepancy between declared table schema and your example data, but it was solved:
1) Setup
-- this the table with the initial data
-- drop table DocumentWordData
create table DocumentWordData
(
Word NVARCHAR(50),
WordCount INT,
DocumentId INT
)
GO
-- these are result table with extra information (identity, primary key constraints, working foreign key definition)
-- drop table WordDictionary
create table WordDictionary
(
Id int IDENTITY(1, 1) CONSTRAINT PK_WordDictionary PRIMARY KEY,
Word nvarchar(50)
)
GO
-- drop table WordDetails
create table WordDetails
(
Id int IDENTITY(1, 1) CONSTRAINT PK_WordDetails PRIMARY KEY,
WordId int CONSTRAINT FK_WordDetails_Word REFERENCES WordDictionary,
WordCount int,
DocumentId int
)
GO
2) The actual script to put data in the last two tables
begin tran
-- this is to make sure that if anything in this block fails, then everything is automatically rolled back
set xact_abort on
-- the dictionary is obtained by considering all distinct words
insert into WordDictionary (Word)
select distinct Word
from DocumentWordData
-- details are generating from initial data joining the word dictionary to get word id
insert into WordDetails (WordId, WordCount, DocumentId)
SELECT W.Id, DWD.WordCount, DWD.DocumentId
FROM DocumentWordData DWD
JOIN WordDictionary W ON W.Word = DWD.Word
commit
-- just to test the results
select * from WordDictionary
select * from WordDetails
I expect this script to run very fast, if you do not have a very large number of records (millions at most).
This is the query. I'm using temp table to be able to test.
if you use the 2 CTEs, you'll be able to generate the final result
1.Setting up a sample data for test.
create table #original (word varchar(10), wordCount int, documentId int)
insert into #original values
('Ball', 10, 1),
('School', 11, 1),
('Car', 4, 1),
('Machine', 3, 1),
('House', 1, 2),
('Tree', 5, 2),
('Ball', 4, 2)
2. Use cte1 and cte2. In your real database, you need to replace #original with the actual table name you have all initial records.
;with cte1 as (
select ROW_NUMBER() over (order by word) Id, word
from #original
group by word
)
select * into #WordDictionary
from cte1
;with cte2 as (
select ROW_NUMBER() over (order by #original.word) Id, Id as wordId,
#original.word, #original.wordCount, #original.documentId
from #WordDictionary
inner join #original on #original.word = #WordDictionary.word
)
select * into #WordDetails
from cte2
select * from #WordDetails
This will be data in #WordDetails
+----+--------+---------+-----------+------------+
| Id | wordId | word | wordCount | documentId |
+----+--------+---------+-----------+------------+
| 1 | 1 | Ball | 10 | 1 |
| 2 | 1 | Ball | 4 | 2 |
| 3 | 2 | Car | 4 | 1 |
| 4 | 3 | House | 1 | 2 |
| 5 | 4 | Machine | 3 | 1 |
| 6 | 5 | School | 11 | 1 |
| 7 | 6 | Tree | 5 | 2 |
+----+--------+---------+-----------+------------+