I'm wondering how I can go about creating a table that won't allow rows to be inserted that are COMPLETE duplicates. By complete I mean every value has to be the same.
I'm okay with inserting rows that are identical other than 1 column's value, but not if they are all the same.
I know you can use INSERT OR IGNORE to avoid inserting duplicate rows, but the problem is that my table uses an auto incremented integer for its primary key, and INSERT OR IGNORE will still allow duplicate rows to be inserted as it sees the auto incremented id as different
Ex.
Running
INSERT OR IGNORE INTO table VALUES ("A", "B" "C");
twice will give me the following table:
id | Column A | Column B | Column C
1. "A" "B" "C"
2. "A" "B" "C"
Is there any way around this other than manually searching rows (ignoring id) for duplicates?
INSERT OR IGNORE will check any constraint, so just add one on the fields you want to check:
CREATE TABLE MyTable(
ColumnA INTEGER PRIMARY KEY,
ColumnB WHATEVER,
ColumnC,
UNIQUE (ColumnA, ColumnB, ColumnC)
);
Related
Please have a look at the following data example:
In this table, I have multiple columns. There is no PRIMARY KEY, as per the image I attached, there are a few duplicates in STK_CODE. Depending on the (min) column, I want to remove duplicate rows.
According to the image, one stk_code has three different rows. Corresponding to these duplicate stk_codes, value in (min) column is different, I want to keep the row which has minimum value in (min) column.
I am very new at sqlite and I am dealing with (-lsqlite3) to join cpp with sqlite.
Is there any way possible?
Your table has rowid as primary key.
Use it to get the rowids that you don't want to delete:
DELETE FROM comparison
WHERE rowid NOT IN (
SELECT rowid
FROM comparison
GROUP BY STK_CODE
HAVING (COUNT(*) = 1 OR MIN(CASE WHEN min > 0 THEN min END))
)
This code uses rowid as a bare column and a documented feature of SQLite with which when you use MIN() or MAX() aggregate functions the query returns that row which contains the min or max value.
See a simplified demo.
I am fairly new to powerbi and I need your help in one task on which I am stuck on.
Basically I have two tables and I need to compare the value from table one with a row of table 2 and return the output.
Table 1
I need to compare values in column a & b and get a match from table 2.
For example if row 1 has BY Green & BS HIGH then I need to check this value from matrix table below and return the output in column value as either 0 or 1.
Table 2
As you can see the Table 2 first row has value BY Green and BS low has a value '0'
Try this...
Index() returns a value from the matrix (in purple) based upon the intersections of the two match()'s. The first is the Vertical match in from the Table1:Col A; the second is the Horizontal match from table1:Col B. The value found at that intersection is returned.
... My apologies ... just saw this was a BI request... no worries...
First, Need fixup table2 as a lookup file:
First, click a cell in table 2 (don't edit), then Data menu >frm table/range, will bring up the Power Query window. Select columns B (not A) through Col F), then in the PQ Transform menu > Unpivot to create the new lookup table. this can either be saved as a new table or be used by reference.
Next, open and merge Table 1 PQ_Table 2 (Be sure to select BOTH Columns in BOTH Tables, in the same order). Then, expand the table tab following the merge expand the table tab. I only selected the value to return but you can return all the values to verify, then delete the unneeded columns.
Hope this helps...
Good Luck.
In Power BI Desktop, I'm trying to order the following column with repeated values by an ID column (contains primary key).
This returns the error: "There can't be more than one value in "Nível2"...."
In this other post it seems the suggestion is to concatenate the values of the column so they don't get duplicate.
But I want them to be repeated so they can aggregate values in visuals.
So, what's the workaround for this situation?
Thanks in advance for helping!
The issue is that your sort column (i.e. your ID column) contains multiple values for each value in the column you are trying to sort (i.e. your Nivel2 column).
You need to ensure that your sort column contains only one distinct value for each value in the column you are trying to sort.
One way to achieve this would be to create a new (calculated) sort column based on your ID column. It could be defined like this:
SortColumn:=CALCULATE(MAX('YourTable'[ID]),ALLEXCEPT('YourTable','YourTable'[Nivel2]))
Here is an example of how the SortColumn would behave:
Id Nivel2 SortColumn
1 Caixa 4
2 Caixa 4
3 Caixa 4
4 Caixa 4
5 Depósitos à ordem 7
6 Depósitos à ordem 7
7 Depósitos à ordem 7
You can now sort Nivel2 by SortColumn.
EDIT - The implementation of the SortColumn should be done in the data source
There seems to be a limitation in PowerBI where it checks the implementation of the sort column rather than the data in the sort column. Therefore the above solution does not work, even though the data in the sort column is perfectly valid. The above solution will throw this error when you attempt to sort [Nivel2] by SortColumn:
This column can't be sorted by a column that is already sorted, directly or indirectly, by this column.
The implementation of the SortColumn should be moved to the data source instead. I.e. if your data source is an Excel sheet, then the SortColumn should be created inside the Excel sheet.
The above answer does explain the issue and the resolvation correctly. The only change is that the SortColumn must be implemented outside of the tabular model (PowerBI) to ensure that PowerBI does not know about the dependency between the SortColumn and the [Nivel2] column.
In my case, I calculate the levels from a parent-child hierarchy
Path = Path([id],[father])
For each level:
Level1 = LOOKUPVALUE([Name],[id], PathItem([Path],1))
Level2 = LOOKUPVALUE([Name],[id], PathItem([Path],2))
.....
Then I created a new column for each level to sort the column Level:
SortL1 = LOOKUPVALUE([nID],[id], PathItem([Path],1))
SortL2 = LOOKUPVALUE([nID],[id], PathItem([Path],2))
.....
id and nID is the same numeric variable but "id" in string format because Path do not support numeric values.
I have a SQLite database.
When writing move rows function, which moves rows from one table to another I need to have a query for incrementing column with name "row" which is INTEGER PRIMARY KEY, but there is an error. It is critical to have indexing with row in my task. The condition in example is WHERE row >= 2 because i am inserting rows from other table into position 2.
"UPDATE '4' SET row = row + 1 WHERE row >= 2"
Error("19", "Unable to fetch row", "UNIQUE constraint failed: 4.row")
The problem's origin WHERE row >= 2" part. How to overcome this problem?
The problem's origin WHERE row >= 2" part.
I'm inclined to disagree. The problem is not with which rows are updated, it is with the order in which they are updated.
Very likely SQLite will process rows in rowid order, which almost certainly is also increasing order of the row column, since that column is an auto-incremented PK. Suppose, then, that the table contains two rows with row values 2 and 3. If it processes the first row first, then it attempts to set that row's row value to 3, but that produces a constraint violation because that column is subject to a uniqueness constraint, and there is already a row with value 3 in that column.
How to overcome this problem?
Do not modify PK values, and especially do not modify the values of surrogate PKs, which substantially all auto-increment keys are.
Alternatively, update the rows into a temporary table, clear the original table, and copy the updated values back into it. This can be extremely messy if you have any FKs referencing this PK, however, so go back to the "Do not modify PK values" advice that I led off with.
First: '4' is not a table name. The UPDATE statement expects a table name where you have written '4'. For example:
UPDATE table1 SET row = row + 1 WHERE row >= 2
Second: Just do not use row as a primary key (or unique key, for that matter) when it obviously is not meant as primary key but as a changing row number. Create a separate column that can be used as primary index of that table instead.
I am using this link.
I have connected my cpp file with Eclipse to my Database with 3 tables (two simple tables
Person and Item
and a third one PersonItem that connects them). In the third table I use one simple primary and then two foreign keys like that:
CREATE TABLE PersonsItems(PersonsItemsId int not null auto_increment primary key,
Person_Id int not null,
Item_id int not null,
constraint fk_Person_id foreign key (Person_Id) references Person(PersonId),
constraint fk_Item_id foreign key (Item_id) references Items(ItemId));
So, then with embedded sql in c I want a Person to have multiple items.
My code:
mysql_query(connection, \
"INSERT INTO PersonsItems(PersonsItemsId, Person_Id, Item_id) VALUES (1,1,5), (1,1,8);");
printf("%ld PersonsItems Row(s) Updated!\n", (long) mysql_affected_rows(connection));
//SELECT newly inserted record.
mysql_query(connection, \
"SELECT Order_id FROM PersonsItems");
//Resource struct with rows of returned data.
resource = mysql_use_result(connection);
// Fetch multiple results
while((result = mysql_fetch_row(resource))) {
printf("%s %s\n",result[0], result[1]);
}
My result is
-1 PersonsItems Row(s) Updated!
5
but with VALUES (1,1,5), (1,1,8);
I would like that to be
-1 PersonsItems Row(s) Updated!
5 8
Can somone tell me why is this not happening?
Kind regards.
I suspect this is because your first insert is failing with the following error:
Duplicate entry '1' for key 'PRIMARY'
Because you are trying to insert 1 twice into the PersonsItemsId which is the primary key so has to be unique (it is also auto_increment so there is no need to specify a value at all);
This is why rows affected is -1, and why in this line:
printf("%s %s\n",result[0], result[1]);
you are only seeing 5 because the first statement failed after the values (1,1,5) had already been inserted, so there is still one row of data in the table.
I think to get the behaviour you are expecting you need to use the ON DUPLICATE KEY UPDATE syntax:
INSERT INTO PersonsItems(PersonsItemsId, Person_Id, order_id)
VALUES (1,1,5), (1,1,8)
ON DUPLICATE KEY UPDATE Person_id = VALUES(person_Id), Order_ID = VALUES(Order_ID);
Example on SQL Fiddle
Or do not specify the value for personsItemsID and let auto_increment do its thing:
INSERT INTO PersonsItems( Person_Id, order_id)
VALUES (1,5), (1,8);
Example on SQL Fiddle
I think you have a typo or mistake in your two queries.
You are inserting "PersonsItemsId, Person_Id, Item_id"
INSERT INTO PersonsItems(PersonsItemsId, Person_Id, Item_id) VALUES (1,1,5), (1,1,8)
and then your select statement selects "Order_id".
SELECT Order_id FROM PersonsItems
In order to achieve 5, 8 as you request, your second query needs to be:
SELECT Item_id FROM PersonsItems
Edit to add:
Your primary key is autoincrement so you don't need to pass it to your insert statement (in fact it will error as you pass 1 twice).
You only need to insert your other columns:
INSERT INTO PersonsItems(Person_Id, Item_id) VALUES (1,5), (1,8)