I have two tables in mysql table1 and table2
table1 have the following fields
Field Type
intProjectId int(11)
intSourceId int(11)
intClientId int(11)
varProject varchar(200)
fltAmount float
varAmountType varchar(50)
dtStart date
dtEnd date
And table 2 have the following fields
Field Type
intPercentageId int(11)
intProjectId int(11)
floatPaymentpercentage float
ddDate datetime
join two table with common project id.If table2 has no records with the particular project id it can joined as null..
Table 1 has project data
Table 2 has its percentage of complettion. (Each project has more than one records. )
Project Id -- common field
Iused the following query
SELECT * FROM table1 LEFT OUTER JOIN table2 ON table1.intProjectId = table2.intProjectId
GROUP BY table1.varProject ORDER BY table2.intPercentageId DESC
Here i get the output as percentage table returns the first record for each project. I need the last inserted record for the table 2.
table1 ==> project id 5
In table 2 has 3 records for project Id 5. I want to ge the last record from the table2. Now it returns the first record from table 2
How to change the query. Please help me to fix this.
Calculate the maximum record for each project in table2 and use that information to get the latest record. Here is a method that uses group by:
select t1.*
from table1 t1 join
table2 t2
on t1.intProjectId = t2.intProjectId join
(select t2.intProjectId, max(intPercentageId) as maxpi
from table2 t2
group by t2.intProjectId
) tt2
on t2.intProjectId = tt2.maxpi;
Calculate the maximum record for each project in table2 and use that information to get the latest record. Here is a method that uses group by:
select t1.*
from table1 t1 join
table2 t2
on t1.intProjectId = t2.intProjectId join
(select t2.intProjectId, max(intPercentageId) as maxpi
from table2 t2
group by t2.intProjectId
) tt2
on t2.intProjectId = tt2.maxpi;
Try this
SELECT * FROM table1 LEFT OUTER JOIN table2 ON table1.intProjectId = table2.intProjectId
GROUP BY table1.varProject HAVING MAX(table2.intPercentageId)
"Order By" runs after "Group by" has completed, that is why it is not giving the intended result. The change I have suggested will give the row from 2nd table with the highest percentage which as per the scenario should be the last row for the project.
Related
I know this involves JOINS but I can't seem to find a working solution to what I'm trying to do.
I have 2 custom tables :
table1 | table2
---------------------
id id
uid uid
track_id track_id
date date
art active
info
blah
blah2
First I want to select everything WHERE uid=55 AND active=1 from table2 :
$tracks = $wpdb->get_results( "SELECT * FROM table2 WHERE uid = 55 AND active = 1");
And then match the track_id from table2 with results from table1 so I can traverse the table1 data.
I know I can do it like this :
foreach( $tracks as $track ) {
$this_track = $track->track_id;
$results = $wpdb->get_results( "SELECT * FROM table1 WHERE track_id = $this_track");
// Do stuff here
}
But this is the part where it gets tricky...
I then want to ORDER the $results from table1 by date DESC from table2
And this is where I'm lost...
Effectively I want (pseudo code) :
$results = $wpdb->get_results( "SELECT * FROM table1 WHERE track_id = $this_track" ORDER BY date DESC FROM table2);
As well as that last bit, I know I can do this entire routine with JOINS to keep this all in one query and make it way more efficient but I just don't know how.
So just to be clear, my overall routine should be like this :
Get all instances of track_id from table2 where user_id=55 and active=1, then use those results to match the track_id to every result in table1 with the same track_id and then sort the results by date back over from table2
Psuedo code, I know it contains nonsense :
$finalresults = $wpdb->get_results( "SELECT * FROM table2 where uid=55 AND active=1 THEN SELECT * FROM table1 WHERE track_id = "the track_id from the first query" THEN ORDER BY date DESC FROM table2);
Try with this query
SELECT t1.* ,t2.date AS t2date, t2.active FROM table2 AS t2 INNER JOIN table1 AS t1 ON (t1.track_id = t2.track_id) WHERE t2.uid=55 AND t2.active=1 ORDER BY t2.date DESC;
Edit: Explanation of what this query is doing. and inverted the order of the tables retrieved in the query (this don't affect the final datatset, i did this to make to follow the logic of the explanation.
1.- Begin with retrieving all rows from table2 (theres is no specific reason because i used table2 over table1, I'm only following an logical order), using the criteria that you specified iud=55 and active=1
SELECT * FROM table2 WHERE uid=55 AND active=1;
2.- but as you said you need to expand the data retrieved in table2 with some information in table1, that's exactly what it is the directive JOIN made, and we are using INNER JOIN because this type of JOIN will show rows ONLY if data for the uid=55 is present on table1, if there is NO data for the uid=55 present on both TABLES then mysql wil show empty the recordset (0 Rows selected).
in the ON(...) part I specify which criteria mysql will use to compara both tables for match in this case will compare that track_id on table2 it is the same that the specified on table1, if this codition is met then mysql considers it as a match.
anly for convenience and because i'm adding a Second table i gave an Alias to each one t1 and t2.
then the query now seems like this
SELECT * FROM table2 AS t2 INNER JOIN table1 AS t1 ON(t1.track.id = t2.track_id) WHERE t2.uid=55 AND t2.active=1;
3.- but then raise a problem, both tables has rows with the same field names, and this is something that DBMS don't like in their queries, to avoid this situation in the query i only show the fields (id, uid and track_id) from one table in this case t1 (t1.*) and only show the fields that doesn't have this problem from t2 (t2.date AS t2date, t2.active). in this way mysql won't throw any error.
SELECT t1.* ,t2.date AS t2date, t2.active FROM table2 AS t2 INNER JOIN table1 AS t1 ON (t1.track_id = t2.track_id) WHERE t2.uid=55 AND t2.active=1;
4.- for the final step i specify to mysql that i want all found rows ordered descent by a field in the table2;
ORDER BY t2.date DESC;
then this criteria will be applied to the whole selected rows. and the final query has this form.
SELECT t1.* ,t2.date AS t2date, t2.active FROM table2 AS t2 INNER JOIN table1 AS t1 ON (t1.track_id = t2.track_id) WHERE t2.uid=55 AND t2.active=1 ORDER BY t2.date DESC;
if is not completely clear you can ask ...
I have two tables, 1st table holds the categories list and 2nd table holds the profile information along with 1st table category id as a foreign key. As follow
Table1
id CATEGORY
1 first
2 second
Table2
id CATEGORY name phone
1 2 John 9999999999
how to retrieve table 2 records along with category name (not id:2 as shown in table 2)
I tried this,
SELECT category, name, phone FROM table2;
I need to see following line as result
second, john, 9999999999
get me out of this step, thanks in advance.
What you need is a JOIN, which means you "combine" two tables by linking rows from one table to rows from another table based on some criterion.
In your case, the criterion is that the value of CATEGORY in table2 must equal the value of ID in table1, which is expressed as follows:
SELECT table1.category,
table2.name,
table2.phone
FROM table2
JOIN table1
ON table2.category = table1.id
If needed, you can add a WHERE clause to limit the result to specific rows, e.g. WHERE table1.id = 9999999999 would filter the rows that have category 9999999999.
This should work:
SELECT t1.category, t2.name, t2.phone
FROM table2 AS t2
JOIN table1 AS t1
ON t1.id = t2.category
You can make an INNER JOIN and get the category from the Table 1, like this:
SELECT tb1.category, tb2.name, tb2.phone
FROM table2 tb2
INNER JOIN table1 tb1 on tb2.category = tb1.id
WHERE tb2.id = 1;
Hope it helps!
I have the below table (in picture) which is kind of inventory table and shows how many items comes in and how many goes out from stock, and item_id is the foreign key from another table.
I want to select those records that has no out from the stock, in other word i want to select those records which are highlighted in green (in the picture).
Thanks.
Sorry for poor English
The Table
Try this:
Select * from `table` where id in (select id from `table`group by id having sum(out)=0);
for deleting those values use:
delete t1
from `your_table` as t1
join (select item_id from `your_table`group by item_id having sum(item_out)=0) t2 on t1.item_id = t2.item_id
Try this query.
SELECT * FROM 'table_name' where out=0;
You need to join the table to itself: SELECT t.* FROM <your_table> AS t LEFT JOIN <your_table> AS t1 ON t.item_id=t1.item_id WHERE t1.out>0 AND t1.item_id IS NULL
I am having a problem with not been able to display all records from table1.
I have 2 tables.
Table 1 and 2 and I want to display all the records from table 1 (Even if some records donly exists on table1 and no reference in table2)
This is what I am trying and I have 2 recording in Table1 but it's only displaying 1.
1 record is joined by the name_id on table1 and table2 and the other record only exists on table1 BUT I need to display both.
Here is the query:
$query = mysql_query("SELECT
table1.name_id,
table2.name_id,
FROM `table1`
LEFT JOIN `table2` ON table1.name_id=table2.name_id
");
How can I get it so it will display all the records from table1 (The one's that are join and the ones that are not too) ?
you can use "JOIN" to fetch data from both table as
$query = mysql_query("SELECT table1.name_id, table2.name_id FROM `table1` JOIN `table2` ON `table1`.`name_id`=`table2`.`name_id` ");
I have two tables Table1 and Table2 with some records
id is the common column in both tables and primarykey is set to this column in table1
There are many records in table1 and some of these records (not all) are updated into table2.
Now I want retrieve from table1 the records not updated into the table2.
For example in table1 there are records 1,2,3,4,5,6,7,8,9
And in table2 there are 3,4,7,9
Now How can I retrieve these records form table1 1,2,5,6 those not updated into table2
I wrote this query :
SELECT Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME
FROM [Table1] INNER JOIN Table2 ON Table1.SLIPNO <>Table2.id;
But the expected result not coming. This query lists all the records repeating each one record manytimes
Can any body give me solution to get the expected result.
select *
from table1
where table1.slip_no NOT IN (select id from table2)
Assuming name of common column is id
Or you can modify your query as
SELECT distinct (Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME)
FROM [Table1]
INNER JOIN Table2 ON Table1.SLIPNO <>Table2.id
A good reference on SQL joins
SELECT t1.*
FROM table1 AS t1
LEFT OUTER JOIN table2 AS t2 USING(id)
WHERE
t2.id IS NULL;
You can use the NOT IN operator on a subquery for table2.
Alternatively, use MINUS with two regular queries listing the ids in each table:
SELECT id FROM table1
MINUS
SELECT id FROM table2;
Try this
SELECT Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME FROM [Table1]
WHERE
NOT EXISTS (SELECT * from Table2 WHERE Table1.SLIPNO !=Table2.id );
You can use the following query
SELECT id FROM database1.table WHERE id NOT IN(SELECT id FROM database2.table)
SELECT child_table.id FROM child_table LEFT JOIN parent_table ON child_table.parent_id = parent_table.id WHERE parent_table.id IS NULL
This left join query returns all the records of the child_table when there is no match in the parent_table. When there is no match, all parent_table fields will be NULL.
inner join will not help. To get unmatched records I tried this:
SELECT
A.ID,A.DATE,A.NAME
FROM TABLE1 A
WHERE CONCAT(A.ID , A.DATE ,A.NAME)
NOT IN
(SELECT CONCAT(B.ID , B.DATE ,B.NAME) as X
from TABLE2 B) ;