I have a MySQL database that I normalized and the idea is to allow for a business to select zero or more marketing sequences, but the kicker is that a handful of marketing sequences are required (right now I have 4, but the list can grow). So what I've done is structured my tables as such:
sequence
+-------------+------------------+-------+-------------+----------+
| sequence_id | customer_type_id | title | description | required |
| 1 | 1 | ... | ... | true |
| 2 | 1 | ... | ... | true |
| 3 | 1 | ... | ... | false |
| 4 | 2 | ... | ... | true |
| 5 | 3 | ... | ... | true |
| 6 | 4 | ... | ... | false |
+-------------+------------------+-------+-------------+----------+
business_sequence
+----------------------+-------------+-------------+
| business_sequence_id | business_id | sequence_id |
+----------------------+-------------+-------------+
customer_type_id and business_id are foreign key fields that link to tables that describe the type of customer (customer, former customer, etc.) and the business's information (name, address, etc.) respectively.
The reason why I have the required column in my sequence table is so that if a business decides not to allow for any of the non-required sequences, then that business would not need a row. After all, there's no need to have duplicate rows in the business_sequence table if the only piece of data that is different is the business_id field.
Now what I'm trying to do is get all the rows and all the fields from the sequence table where the business_id in the business_sequence table matches a parameterized value (say 1 for the example that I'm going to show in a second). The query that I tried to use is:
SELECT
s.*
FROM
`sequence` AS s
INNER JOIN `business_sequence` AS b ON b.`sequence_id` = s.`sequence_id`
WHERE
b.`business_id` = 1 AND
s.`required` = true;
But this returned no results if the business had no rows in the sequence table. What I expected it to do is return the 0 rows from the b.business_id = 1 but I also expected it to return the 4 "required" rows (ids: 1, 2, 4, and 5) from the s.required = true.
Whenever I took out the INNER JOIN statement and the business_id portion of the WHERE clause, it does in fact return the 4 "required" rows. This leads me to believe that in my original query, because there are no rows for that particular business_id in the sequence table it isn't returning anything.
With all of this being said, how do I accomplish retrieving the zero or more rows when the business_id field matches the parameterized value and retrieve all of the rows when the required field is true?
How about using OR condition in stead of AND ?
SELECT
s.*
FROM
`sequence` AS s
INNER JOIN `business_sequence` AS b ON b.`sequence_id` = s.`sequence_id`
WHERE
b.`business_id` = 1 OR
s.`required` = true;
I was able to resolve my problem by performing a UNION as such:
SELECT * FROM `sequence` WHERE `required` = true
UNION
SELECT
s.*
FROM
`sequence` AS s
INNER JOIN `business_sequence` AS b ON b.`sequence_id` = s.`sequence_id`
WHERE
b.`business_id` = 1
Related
I have a record table and its comment table, like:
| commentId | relatedRecordId | isRead |
|-----------+-----------------+--------|
| 1 | 1 | TRUE |
| 2 | 1 | FALSE |
| 3 | 1 | FALSE |
Now I want to select newCommentCount and allCommentCount as a server response to the browser. Is there any way to select these two fields in one SQL?
I've tried this:
SELECT `isRead`, count(*) AS cnt FROM comment WHERE relatedRecordId=1 GROUP BY `isRead`
| isRead | cnt |
| FALSE | 2 |
| TRUE | 1 |
But, I have to use a special data structure to map it and sum the cnt fields in two rows to get allCommentCount by using an upper-layer programming language. I want to know if I could get the following format of data by SQL only and in one step:
| newCommentCount | allCommentCount |
|-----------------+-----------------|
| 2 | 3 |
I don't even know how to describe the question. So I got no any search result in Google and Stackoverflow. (Because of My poor English, maybe)
Use conditional aggregation:
SELECT SUM(NOT isRead) AS newCommentCount, COUNT(*) AS allCommentCount
FROM comment
WHERE relatedRecordId = 1;
if I under stand you want show sum of newComments Count and all comments so you can do it like
SELECT SUM ( CASE WHEN isRead=false THEN 1 ELSE 0 END ) AS newComment,
Count(*) AS AllComments From comments where relatedRecord=1
also you can make store procedure for it.
To place two result sets horizontally, you can as simple as use a subquery for an expression in the SELECT CLAUSE as long as the number of rows from the result sets match:
select (select count(*) from c_table where isread=false and relatedRecordId=1 ) as newCommentCount,
count(*) as allCommentCount
from c_table where relatedRecordId=1;
I have two existing table and wants to create third table with help of few columns. The fist two tables are;
Table one: users
|id | name | sid |
| 1 | demo | test1 |
| 2 | anu | test2 |
Table one: insights
| id | description| name |
| 1 | yes | demoone|
| 2 | no | demotwo|
I want to insert data in new table called insight_owner. As per my knowledge, I made below query but that is giving me below error
ERROR 1242 (21000): Subquery returns more than 1 row
The query used is
insert into insight_owner (column_one, column_two, column_three, column_four, column_five) VALUES ('1', '0', NULL, (select u.id from users u where u.sid='test1'), (select i.id from insights i)) ;
Expected output is
| column_one| column_two| column_three| column_four| column_five| column_six |
+----+-----------------+--------------------+---------------+-----------+--------------------+
| 1 | 1 | 1 | NULL | 1 | 1 |
| 2 | 1 | 1 | NULL | 1 | 2 |
column_five = Users id
column_six = Insight id
INSERT...SELECT syntax is what you're looking for (instead of INSERT...VALUES, which is limited to single values per column in each value list). That allows you to select the data directly from the table(s) concerned, using normal SELECT and JOIN syntax. You can also hard-code values which you want to appear on every row, just as you can in a normal SELECT statement. Basically, write the SELECT statement, get it to output what you want. Then stick an INSERT at the start of it and it sends the output to the desired table.
insert into insight_owner (column_one, column_two, column_three, column_four, column_five)
select '1', '0', NULL, (select u.id from users u where u.sid='test1'), i.id
from insights i
You are using
insert into insight_owner (column_one, column_two, column_three, column_four, column_five) VALUES ('1', '0', NULL, (select u.id from users u where u.sid='test1'), (select i.id from insights i));
Which basically inserts one row in your new table.
So, when you add subquery
select i.id from insights i
It will return all rows from insights table an you actually want just one value.
The result you will get is
| id |
| 1 |
| 2 |
And you want
| id |
| 1 |
So, you should be adding conditional that will make sure you are getting only one result as you are doing with first query (where u.sid='test1'), or limit.
I hope this helps.
I have two tables with the following structures (unnecessary columns trimmed out)
----------------- ---------------------
| mod_personnel | | mod_skills |
| | | |
| - prs_id | | - prs_id |
| - name | | - skl_id |
----------------- | |
---------------------
There may be 0 to many rows in the skills table for each prs_id
What I want is all the personnel records which do NOT have an associated skill record with skill_id 1.
In plain English "I want all the people who do not have the skill x".
Currently, I have only been able to do it with the following nested select. But I am hoping to find a faster way.
SELECT * FROM `mod_personnel` WHERE `prs_id` NOT IN (
SELECT `prs_id` FROM `mod_skills` WHERE `skl_id` = 1 )
This may be faster:
SELECT `mod_personnel`.*
FROM `mod_personnel`
left outer join `mod_skills`
on `mod_skills`.`prs_id` = `mod_personnel`.`prs_id`
and `mod_skills`.`skl_id` = 1
WHERE `mod_skills`.`prs_id` is null;
Using a NOT EXISTS might be faster.
SELECT *
FROM `mod_personnel` p
WHERE NOT EXISTS (SELECT *
FROM `mod_skills` s
WHERE s.`prs_id` = p.`prs_id`
AND s.`skl_id` = 1 );
I have two mysql tables record_items,property_values with the following structure.
table : property_values (column REC is foreign key to record_items)
id(PK)|REC(FK)| property | value|
1 | 1 | name | A |
2 | 1 | age | 10 |
3 | 2 | name | B |
4 | 3 | name | C |
5 | 3 | age | 9 |
table: record_items
id(PK) |col1|col2 |col3|
1 | v11| v12 | v13|
2 | v21| v22 | v23|
3 | v31| v32 | v33|
4 | v41| v42 | v43|
5 | v51| v52 | v53|
record_items table contains only basic information about the record, where as property_values table keeps record_item as a foreign key and each property and its value is saved in a separate row.
Now I want to get the record_items sorted based on a particular property, say by age.
My HQL query will be like
Select distinct rec from PropertyValues where property="age" order by value;
But this query will be skipping record 2 since it don't have an entry for property age.
I expect the result to have the records which contains age property in sort order appended by those which don't have age property at all. How can I query that?
Here is a raw MySQL query which should do the trick:
SELECT t1.*
FROM record_items t1
LEFT JOIN property_values t2
ON t1.id = t2.REC AND
t2.property = 'age'
ORDER BY CASE WHEN t2.value IS NULL THEN 1 ELSE 0 END, t2.Value
I notice that your Value column in property_values is mixing numeric and text data. This won't work well for sorting purposes.
Demo here
Background
I have a web application which must remove entries from other tables, filtered through a selection of 'tielists' from table 1 -> item_table 1, table 2, table 3.... now basically my result set is going to be filthy big unless I use a filter statement from another table, using a user_id... so can someone please help me structure my statement as needed? TY!
Tables
cars_belonging_to_user
-----------------------------
ID | user_id | make | model
----------------------------
1 | 1 | Toyota | Camry
2 | 1 |Infinity| Q55
3 | 1 | DMC | DeLorean
4 | 2 | Acura | RSX
Okay, Now the three 'tielists'
name:tielist_one
----------------------------
id | id_of_car | id_x | id_y|
1 | 1 | 12 | 22 |
2 | 2 | 23 | 32 |
-----------------------------
name:tielist_two
-------------------------------
id | id_of_car | id_x | id_z|
1 | 3 | 32 | 22 |
-----------------------------
name: tielist_three
id | id_of_car | id_x | id_a|
1 | 4 | 45 | 2 |
------------------------------
Result Set and Code
echo name_of_tielist_table
// I can structure if statements to echo result sets based upon the name
// Future Methodology: if car_id is in tielist_one, delete id_x from x_table, delete id_y from y_table...
// My output should be a double select base:
--SELECT * tielists from WHERE car_id is 1... output name of tielist... then
--SELECT * from specific_tielist where car_id is 1.....delete x_table, delete y_table...
Considering the list will be massive, and the tielist equally long, I must filter the results where car_id(id) = $variable && user_id = $id....
Side Notes
Only one car id will appear once in any single tielist..
This select statement MUST be filtered with user_id = $variable... (and remember, i'm looking for which car id too)
I MUST HAVE THE NAME of the tielist it comes from able to be echo'd into a variable...
I will only be looking for one single id_of_car at any given time, because this select will be contained in a foreach loop.
I was thinking a union all items would do the trick to select the row, but how can I get the name of the tielist the row is in, and how can the filter be used from the user_id row
If you want performance, I would suggest left outer join instead of union all. This will allow the query to make efficient use of indexes for your purpose.
Based on what you say, a car is in exactly one of the lists. This is important for this method to work. Here is the SQL:
select cu.*,
coalesce(tl1.id_x, tl2.id_x, tl3.id_x) as id_x,
tl1.y, tl2.idz, tl3.id_a,
(case when tl1.id is not null then 'One'
when tl2.id is not null then 'Two'
when tl3.id is not null then 'Three'
end) as TieList
from Cars_Belonging_To_User cu left ouer join
TieList_One tl1
on cu.id_of_car = tl1.id_of_car left outer join
TieList_Two tl2
on cu.id_of_car = tl2.id_of_car left outer join
TieList_Three tl3
on cu.id_of_car = tl3.id_of_car;
You can then add a where clause to filter as you need.
If you have an index on id_of_car for each tielist table, then the performance should be quite good. If the where clause uses an index on the first table, then the joins and where should all be using indexes, and the query will be quite fast.