how to make this work in mysql?
select ID,COMPANY_NAME,contact1, SUBURB, CATEGORY, PHONE from Victoria where (city in ( select suburb from allsuburbs)) and CATEGORY='Banks'
this below statement is working:
select ID,COMPANY_NAME,contact1, SUBURB, CATEGORY, PHONE from Victoria where city in ( select suburb from allsuburbs)
if I add "and" , it gives me an empty resultset,
thanks
Learn how joins work.
select
v.ID,v.COMPANY_NAME,v.contact1,v.SUBURB,v.CATEGORY,v.PHONE
from
Victoria v
inner join allsuburbs s on s.suburb = v.city
where
v.CATEGORY='Banks'
Apart from that, your query does not make a whole lot of sense.
Your table is namend Victoria, but it contains a field named city?! Do your other cities have their own table too?
You have a table named allsuburbs, but your criterion is that Victoria.city equals allsuburbs.suburb, even though a field named Victoria.suburb exists?! What's Victoria.suburb for, then?
Your table is named allsuburbs. Do you have another table that contains suburbs or is this your only one? If it is your only one, the name is redundant.
You have a field contact1. Do you have contact2...contact10 as well? Bad database design.
Why is half of your fieldnames in caps, and not all of them (or none of them)?
Oh, and the usual format for SQL is: SQL keywords in caps, the field names etc. in mixed case/lower case. Much easier to read.
I think you might have misplaced a parentheses?
.. PHONE from Victoria where
(city in ( select suburb from allsuburbs)) and CATEGORY='Banks'
I'm guessing should be:
.. PHONE from Victoria where
city in ( select suburb from allsuburbs) and CATEGORY='Banks'
Not sure if that makes more sense, but the first case is not an ok SQL-statement I believe.
Related
So I have a query that shows a huge amount of mutations in postgres. The quality of data is bad and i have "cleaned" it as much as possible.
To make my report so user-friendly as possible I want to filter out some rows that I know the customer don't need.
I have following columns id, change_type, atr, module, value_old and value_new
For change_type = update i always want to show every row.
For the rest of the rows i want to build some kind of logic with a combination of atr and module.
For example if the change_type <> 'update' and concat atr and module is 'weightperson' than i don't want to show that row.
In this case id 3 and 11 are worthless and should not be shown.
Is this the best way to solve this or does anyone have another idea?
select * from t1
where concat(atr,module) not in ('weightperson','floorrentalcontract')
In the end my "not in" part will be filled with over 100 combinations and the query will not look good. Maybe a solution with a cte would make it look prettier and im also concerned about the perfomance..
CREATE TABLE t1(id integer, change_type text, atr text, module text, value_old text, value_new text) ;
INSERT INTO t1 VALUES
(1,'create','id','person',null ,'9'),
(2,'create','username','person',null ,'abc'),
(3,'create','weight','person',null ,'60'),
(4,'update','id','order','4231' ,'4232'),
(5,'update','filename','document','first.jpg' ,'second.jpg'),
(6,'delete','id','rent','12' ,null),
(7,'delete','cost','rent','600' ,null),
(8,'create','id','rentalcontract',null ,'110'),
(9,'create','tenant','rentalcontract',null ,'Jack'),
(10,'create','rent','rentalcontract',null ,'420'),
(11,'create','floor','rentalcontract',null ,'1')
Fiddle
You could put the list of combinations in a separate table and join with that table, or have them listed directly in a with-clause like this:
with combinations_to_remove as (
select *
from (values
('weight', 'person'),
('floor' ,'rentalcontract')
) as t (atr, module)
)
select t1.*
from t1
left join combinations_to_remove using(atr, module)
where combinations_to_remove.atr is null
I guess it would be cleaner and easier to maintain if you put them in a separate table!
Read more on with-queries if that sounds strange to you.
I'm having trouble creating a query for the following task: i want to return exactly one row with columns: region_id, region_name, province_name, province_code, country_name, country_code for any given regionid. The database has 3 tables "countrylist" , "provinces" and "regionlist"
the table countrylist has the following columns : countryid, language code, countryname, countrycode and continentid
provinces : country_code, country_name, province_code, province_name
regionlist: regionid, regiontype.
So I tried writing a query for joining the table but I'm sure if I'm doing it correct.
exactly one row with columns: region_id, region_name, province_name, province_code, country_name, country_code for any given regionid.
I am not 100% aware of the differences between Postgres and MySQL - but guess you get the idea at the very least.
One way to do it, to get your id with WHERE regionlist.regionid = and join the other tables. From either the regionlist you can use the LIMIT (reference) to get a limited amount of rows.
Apparently neither provinces nor country have a common column with regionlist, so I can not tell where the link between those are. However, once you have 1 row of the region list you should have no troubles joining them with the others (if the links are trivial).
I am joining two tables house and tower, both have some of the same column names such as id, created_at, deleted, address etc. I wonder if it is possible to return the columns in the following fashion: house.created_at, house.id, tower.created_at, tower.id etc. I know I can query with AS, I was wondering if it is possible to query something like this: SELECT house.* AS house, tower.* AS tower. I tried it like this, but it was not valid SQL. Any idea how I can chase the column names prefix easily ?
I have created a database as part of university assignment and I have hit a snag with the question in the title.
More likely I am being asked to find out how many films each company has made. Which suggests to me a group by query. But I have no idea where to begin. It is only a two mark question but the syntax is not clicking in my head.
My schema is:
CREATE TABLE Movie
(movieID CHAR(3) ,
title CHAR(36),
year NUMBER,
company CHAR(50),
totalNoms NUMBER,
awardsWon NUMBER,
DVDPrice NUMBER(5,2),
discountPrice NUMBER(5,2))
There are other tables but at first glance I don't think they are relevant to this question.
I am using sqlplus10
The answer you need comes from three basic SQL concepts, I'll step through them with you. If you need more assistance to create an answer from these hints, let me know and I can try to keep guiding you.
Group By
As you mentioned, SQL offers a GROUP BY function that can help you.
A SQL Query utilizing GROUP BY would look like the following.
SELECT list, fields, aggregate(value)
FROM tablename
--WHERE goes here, if you need to restrict your result set
GROUP BY list, fields
a GROUP BY query can only return fields listed in the group by statement, or aggregate functions acting on each group.
Aggregate Functions
Your homework question also needs an Aggregate function called Count. This is used to count the results returned. A simple query like the following returns the count of all records returned.
SELECT Count(*)
FROM tablename
The two can be combined, allowing you to get the Count of each group in the following way.
SELECT list, fields, count(*)
FROM tablename
GROUP BY list, fields
Column Aliases
Another answer also tried to introduce you to SQL column aliases, but they did not use SQLPLUS syntax.
SELECT Count(*) as count
...
SQLPLUS column alias syntax is shown below.
SELECT Count(*) "count"
...
I'm not going to provide you the SQL, but instead a way to think about it.
What you want to do is select where the company matches and count the total rows returned. That count is the number of films made by the specified company.
Hope that points you in the right direction.
Select company, count(*) AS count
from Movie
group by company
select * group by company won't work in Oracle.
I have a problem with TSQL. I have a number of tables, each table contain different number of fielsds with different names.
I need dynamically take all this tables, read all records and manage each record into string list, where each value separated by commas. And do smth. with this string.
I think that I need to use CURSORS, but I can't FETCH em without knowing A concrete amount of fields with names and types. Maybe I can create a table variable with dynamic number of fields?
Thanks a lot!
Makarov Artem.
I would repurpose one of the many T-SQL scripts written to generate INSERT statements. They do exactly what you require. Namely
Reverse engineer a given table to determine columns names and types
Generate a delimited string of values
The most complete example I've found is here
But just a simple Google search for "INSERT STATEMENT GENERATOR" will yield several examples that you can repurpose to fit your needs.
Best of luck!
SELECT
ORDINAL_POSITION
,COLUMN_NAME
,DATA_TYPE
,CHARACTER_MAXIMUM_LENGTH
,IS_NULLABLE
,COLUMN_DEFAULT
FROM
INFORMATION_SCHEMA.COLUMNS
WHERE
TABLE_NAME = 'MYTABLE'
ORDER BY
ORDINAL_POSITION ASC;
from http://weblogs.sqlteam.com/joew/archive/2008/04/27/60574.aspx
Perhaps you can do something with this.
select T2.X.query('for $i in *
return concat(data($i), ",")'
).value('.', 'nvarchar(max)') as C
from (
select *
from YourTable
for xml path('Row'),elements xsinil, type
) as T1(X)
cross apply T1.X.nodes('/Row') T2(X)
It will give you one row for each row in YourTable with each value in YourTable separated by a comma in the column C.
This builds an XML for the entire table and then parses that XML. Might get you into trouble if you have tables with a lot of rows.
BTW: I saw from a comment that you can "use only pure SQL". I really don't think this qualifies as "pure SQL" :).