MySQL only one active record, multiple inactive records - mysql

I've got this MySQL-table:
id | staffId | companyId | active | somevalue
When I create an UNIQUE index on staffId, companyId and active I can store a maximum of two records. One with active 1 and one with active 0.
I would like to make sure I can have only one active record while it is possible to have multiple inactive records. For example:
1 | 1 | 1 | 1 | 1
1 | 1 | 1 | 0 | 5
1 | 1 | 1 | 0 | 7
Should be possible, but adding this record should cause an error:
1 | 1 | 1 | 1 | 9

Choosing NULL instead of 0 for an incactive record seems to work :-) I wonder if there are better solutions?

Related

Getting count of insert/update rows from ON DUPLICATE KEY UPDATE

I have a statement that tries to insert a record and if it already exists, it simply updates the record.
INSERT INTO temptable (col1,col2,col3)
VALUES (1,2,3)
ON DUPLICATE KEY UPDATE col1=VALUES(col1), col2=VALUES(col2), col3=VALUES(col3);
The full statement has multiple inserts and I'm looking to count number of INSERTs against the UPDATEs. Can I do this with MySQL variables, I've yet to find a way to do this after searching.
From Mysql Docs
In the case of "INSERT ... ON DUPLICATE KEY UPDATE" queries, the return value will be 1 if an insert was performed, or 2 for an update of an existing row.
Use mysql_affected_rows() after your query, if INSERT was performed it will give you 1 and if UPDATE was performed it will give you 2.
I've accomplished what you're describing using a while loop so that each iteration creates a MySQL statement that affects one row. Within the loop, I run the mysql_affected_rows() and then increment a counter depending upon whether the value returned was a 0 or a 1. At the end of the loop, I echo both variables for viewing.
The complete wording from MySQL Docs regarding the mysql_affected_rows function is (notice there are 3 possible values returned - 0, 1, or 2):
For INSERT ... ON DUPLICATE KEY UPDATE statements, the affected-rows
value per row is 1 if the row is inserted as a new row, 2 if an
existing row is updated, and 0 if an existing row is set to its
current values. If you specify the CLIENT_FOUND_ROWS flag, the
affected-rows value is 1 (not 0) if an existing row is set to its
current values.
(Sidenote - I set $countUpdate and $countInsert and $countUpdateNoChange to 0 prior to the while loop):
Here's the code that I developed that works great for me:
while (conditions...) {
$sql = "INSERT INTO test_table (control_number, name) VALUES ('123', 'Bob')
ON DUPLICATE KEY UPDATE name = 'Bob'";
mysql_query($sql) OR die('Error: '. mysql_error());
$recordModType = mysql_affected_rows();
if ($recordModType == 0) {
$countUpdateNoChange++;
}elseif($recordModType == 1){
$countInsert++;
}elseif($recordModType == 2){
$countUpdate++;
};
};
echo $countInsert." rows inserted<br>";
echo $countUpdateNoChange." rows updated but no data affected<br>";
echo $countUpdate." rows updated with new data<br><br>";
Hopefully, I haven't made any typos as I've recreated it to share while removing my confidential data.
Hope this helps someone. Good luck coding!
I know this is a bit old, but I was doing a bulk insert in PHP and needed to know exactly how many rows were inserted and updated (separately).
So I used this:
$dataCount = count($arrData); // number of rows in the statement
$affected = mysql_affected_rows(); // mysqli_*, PDO's rowCount() or anything
$updated = $affected - $dataCount;
$inserted = 2 * $dataCount - $affected;
Simple trace table:
-------------------------------
| data | affected | ins | upd |
-------------------------------
| 1 | 1 | 1 | 0 |
-------------------------------
| 2 | 2 | 2 | 0 |
| 2 | 3 | 1 | 1 |
| 2 | 4 | 0 | 2 |
-------------------------------
| 3 | 3 | 3 | 0 |
| 3 | 4 | 2 | 1 |
| 3 | 5 | 1 | 2 |
| 3 | 6 | 0 | 3 |
-------------------------------
| 4 | 4 | 4 | 0 |
| 4 | 5 | 3 | 1 |
| 4 | 6 | 2 | 2 |
| 4 | 7 | 1 | 3 |
| 4 | 8 | 0 | 4 |
-------------------------------
| 5 | 5 | 5 | 0 |
| 5 | 6 | 4 | 1 |
| 5 | 7 | 3 | 2 |
| 5 | 8 | 2 | 3 |
| 5 | 9 | 1 | 4 |
| 5 | 10 | 0 | 5 |
-------------------------------
if you want to get the number of records that have been inserted and updated separetly, you are to issue each statement separetly.

Sort table records in special order

I have table:
+----+--------+----------+
| id | doc_id | next_req |
+----+--------+----------+
| 1 | 1 | 4 |
| 2 | 1 | 3 |
| 3 | 1 | 0 |
| 4 | 1 | 2 |
+----+--------+----------+
id - auto incerement primary key.
nex_req - represent an order of records. (next_req = id of record)
How can I build a SQL query get records in this order:
+----+--------+----------+
| id | doc_id | next_req |
+----+--------+----------+
| 1 | 1 | 4 |
| 4 | 1 | 2 |
| 2 | 1 | 3 |
| 3 | 1 | 0 |
+----+--------+----------+
Explains:
record1 with id=1 and next_req=4 means: next must be record4 with id=4 and next_req=2
record4 with id=5 and next_req=2 means: next must be record2 with id=2 and next_req=3
record2 with id=2 and next_req=3 means: next must be record3 with id=1 and next_req=0
record3 with id=3 and next_req=0: means that this is a last record
I need to store an order of records in table. It's important fo me.
If you can, change your table format. Rather than naming the next record, mark the records in order so you can use a natural SQL sort:
+----+--------+------+
| id | doc_id | sort |
+----+--------+------+
| 1 | 1 | 1 |
| 4 | 1 | 2 |
| 2 | 1 | 3 |
| 3 | 1 | 4 |
+----+--------+------+
Then you can even cluster-index on doc_id,sort for if you need to for performance issues. And honestly, if you need to re-order rows, it is not any more work than a linked-list like you were working with.
Am able to give you a solution in Oracle,
select id,doc_id,next_req from table2
start with id =
(select id from table2 where rowid=(select min(rowid) from table2))
connect by prior next_req=id
fiddle_demo
I'd suggest to modify your table and add another column OrderNumber, so eventually it would be easy to order by this column.
Though there may be problems with this approach:
1) You have existing table and need to set OrderNumber column values. I guess this part is easy. You can simply set initial zero values and add a CURSOR for example moving through your records and incrementing your order number value.
2) When new row appears in your table, you have to modify your OrderNumber, but here it depends on your particular situation. If you only need to add items to the end of the list then you can set your new value as MAX + 1. In another situation you may try writing TRIGGER on inserting new items and calling similar steps to point 1). This may cause very bad hit on performance, so you have to carefully investigate your architecture and maybe modify this unusual construction.

How to update a 'Sort Index' column of a list of records with one call

Basically, I have a list of records in a mysql db. These records are ordered 1 to 10. The user can re-order these records to whatever order they want. They will press a button to update all the records to their newly, respective order number. For example:
ID | Sort_Index | Name
----------------------
1 | 1 | Jim
2 | 2 | Bob
3 | 3 | Carl
4 | 4 | Bill
5 | 5 | Wendy
The user can change these to this for example:
Note: the changed values are stored into an array before I make the UPDATE calls
ID | Sort_Index | Name
----------------------
1 | 1 | Carl
2 | 2 | Wendy
3 | 3 | Bob
4 | 4 | Jim
5 | 5 | Bill
My question is, how can I make this mysql call with one call, using the new values in my array, instead of one call for each record?
If this is impossible or simply the "wrong way to do it", please feel free to suggest new ideas as I am not fully committed to this idea as of now.
If you have a limited number of rows, you could implement this with an sql CASE statement --
Update users set sort_index = case id when 1 then <newval> when 2 then <newval>...

Data Entry Tracking (Database Design)

I have developed a website (PHP) that allow staffs to add records on to our system.
Staffs will be adding thousands of records into our database.
I need a way to keep track of what record have been done and the process/status of record.
Here a number of Teams I could think of:
Data Entry Team
Proof Reading Team
Admin Team
When staff (Data Entry Team) completed a record - he/she will then click on the Complete button. Then somehow it should asssign to 'Proof Reading Team' automatically.
A record need to be checked twice from a Proof Reading Team. If StaffB finish proof reading then another member from Proof Reading Team need to check it again.
When Proof reading is done, Admin Team will then assign "Record Completed"
In a few months later record might need to be updated (spelling mistake, price change, etc) - Admin might to assign record to Data entry team.
Is this good data entry management solution? How do I put this into Database Design perspective?
Here what I tried:
mysql> select * from records;
+----+------------+----------------------+
| id | name | address |
+----+------------+----------------------+
| 1 | Bill Gates | Text 1 Text Text 1 |
| 2 | Jobs Steve | Text 2 Text 2 Text 2 |
+----+------------+----------------------+
mysql> select * from staffs;
+----+-----------+-----------+---------------+
| id | username | password | group |
+----+-----------+-----------+---------------+
| 1 | admin1 | admin1 | admin |
| 2 | DEntryA | DEntryA | data_entry |
| 3 | DEntryB | DEntryB | data_entry |
| 4 | PReadingA | PReadingA | proof_reading |
| 5 | PReadingB | PReadingB | proof_reading |
+----+-----------+-----------+---------------+
mysql> select * from data_entry;
+----+------------+-----------+------------------------+
| id | records_id | staffs_id | record_status |
+----+------------+-----------+------------------------+
| 1 | 2 | 3 | data_entry_processiing |
| 2 | 2 | 3 | data_entry_completed |
| 3 | 2 | 4 | proof_read_processing |
| 4 | 2 | 4 | proof_read_completed |
| 5 | 2 | 5 | proof_read_processing |
| 6 | 2 | 5 | proof_read_completed |
+----+------------+-----------+------------------------+
Is there alternative better solution of database design?
i think design it's well done. but may be you want to separate group into groups table, and record_status into status table. If you're storing a lot of records you would store a lot of useless information, at least create an enum type for record_status field and group field
table: groups
id - name 1 - admin 2 - data_entry 3 - proof_reading
...
table: status
id - name 1 - data_entry_processing ...
and if you want the users to be in different groups at a time, you could create users_group table
table: user_groups
group_id - user_id 1 - 1 2 - 1 1 - 4 3 -
4 4 - 4 ....
Hope this helps

Special unique columns

I have a situation where a website (a source) has multiple feeds (category separated)
Feed Table
feed_id | source_id | feed_url
1 | 1 | http://example.com/rss?category=1
2 | 1 | http://example.com/rss?category=5
3 | 2 | http://textample.com/rss
Item Table
item_id | true_id | feed_id
1 | 1332 | 1
2 | 76549 | 1
3 | 76549 | 2
4 | 76549 | 3
the true id is the id I try to get from the source site.
I want the item id 2 & 3 are the same, because they share the same source (example.com), item 4 is not the same because it has a different source (textample.com)
Is there a way I can enforce that consistency, without adding the source id to the Item Table?
RUN
ALTER TABLE `itemTable` ADD UNIQUE (`feed_id`);