In DB we have a field named 'request'.
while updating the values we found that we are having a duplicate values in a single field.
Fo EX:
ID request cust
1 **25**;26;**25**;29;28;23;21;**25**;20 1
2 **24**;26;27;**24**;25;23;**24**;22;22 2
Now in the above table , the values in the field request there are same values in a single field.
now how can i eliminate a duplicate value in it?
If you have to use a delimited list inside a field like this...
You can to:
split the field into into a temp table..
eliminate duplicates from the table
recreate the delimited field from the temp table.
Searching SO will provide method to each step.
You choice will be guided in part by your RDBMS.
Related
I have a table named comments_live which has 4 fields and some 24000 entries. I want to add another field which is the output of a select query. The query is like this:
INSERT INTO comments_live SELECT SUBSTR(record,1, POSITION(' ' IN record)) AS project_id FROM comments_live;
What this query is doing is it's appending the result of the SELECT query to the table. I want the 'project_id' field to be appended to the existing 24000 rows. i.e. The above query should not add those extra rows to the table.
Any help would be appreciated.
PS: I tried adding a empty column 'project_id' to the table first and then executing the query, still I'm getting the same result.
I conclude from your code example that you want to add a column whose content is the substring from the column RECORD. If you succeeded in adding the empty column, then you just need code like the following:
update comments_live
set project_id=substr(record,1,[...])
I am working on a script using SQLite where there is a flux in the number of columns that are available to be inserted into a table I am creating to later do a join on.
The table I am created to insert the data into has 97 columns, the data coming in from my feed can range from around 80 all the way up to that 97th column.
The error I get is SQLITE_ERROR: table allPositionsTable has 97 columns but 80 values were supplied and is the one I am trying to avoid by figuring out a way where this doesn't happen.
Are there any workarounds or tricks I can use to have SQLite function so that it will always include the columns where there is no data for them or dynamically not include them so the error goes away?
The error I get is SQLITE_ERROR: table allPositionsTable has 97
columns but 80 values were supplied and is the one I am trying to
avoid by figuring out a way where this doesn't happen.
This happens because you are using the default column list (i.e. by not specifying the columns into which the values are to be placed)
That is you would be coding the equivalent of INSERT INTO your_table VALUES(.......
so in the absence of a list of columns you are saying that you will provide a value for all columns in the table and hence the message when a value or values are not present.
What you want to do is use INSERT INTO your_table_name (your_comma_separated_list_of_columns_to_be_inserted) VALUES(.......
where your_table_name and your_comma_separated_list_of_columns_to_be_inserted would be replaced with the appropriate values.
See the highlighted section of the INSERT syntax that can be found at SQL As Understood By SQLite - INSERT
and the respective section from the above link is :-
The first form (with the "VALUES" keyword) creates one or more new
rows in an existing table.
If the column-name list after table-name is
omitted then the number of values inserted into each row must be the
same as the number of columns in the table.
In this case the result of
evaluating the left-most expression from each term of the VALUES list
is inserted into the left-most column of each new row, and so forth
for each subsequent expression.
If a column-name list is specified,
then the number of values in each term of the VALUE list must match
the number of specified columns.
Each of the named columns of the new
row is populated with the results of evaluating the corresponding
VALUES expression.
Table columns that do not appear in the column list
are populated with the default column value (specified as part of the
CREATE TABLE statement), or with NULL if no default value is
specified.
I have a table with a 'user_id' column. Within that same table I have another data field labeled 'GMID'. Within that GMID column there are some fields that are null, the ones that aren't null have values that match the user_id data field within that row. Is there a way to create a script or query that will update all null fields in the GMID column to match the corresponding data values in the user_id row within that row? Are there any best practices I should follow, different approaches? Thanks in advance for anyone that can help.
Of course there is
UPDATE your_table
SET GMID=user_id
WHERE GMID IS NULL
But you even don't need WHERE if GMID always should be same as user_id.
By the way, why do you need two columns with same data in one table?
Another approach would be using the 'coalesce' function. It will return the first non-null value. This approach does not involve data changes on your table. On a query you can 'select coalesce(GMID, user_id) as GMID ...' it will return the first column that is not null.
Documentation for oracle DB:
http://docs.oracle.com/cd/B28359_01/server.111/b28286/functions023.htm
Update: I just reversed the name of the columns inside the coalesce function...
I want to copy the content of one column in table A and replace the contents (not insert into it - the number of rows will be the same) of another column in another table.
I can't a where condition, the table has only just been created at this point with one empty timestamp column. it will be populated via pyodbc class after the timestamps have been added - this query will fill the timestamps for me
What is the SQL command for this?
Thanks!
After discussion, this is the query needed : INSERT INTO OCAT_test_table (DateTimeStamp) SELECT DateTimeStamp FROM DunbarGen
I want to make filtration on a column after selecting a specific value of another column in the same table, I tried to use #... special character followed by the column's name to get the address of this value.
My SQL statement is like the following :
SELECT ATTRIBUTE FROM TABLE WHERE FIELD = '#FIELDNAME';
If I used a specific value instead of #FIELDNAME, it will work properly but it will be static but I need it to be dynamic based on the selected value.
Create another table which will have the list of values that are in the FIELDNAME and give each record a unique id ,then retrieve the value depending on what you have selected by the name of the new table's field preceded by '#...'
I don't know if that what are you looking for, please let me know.
If no triggers are allowed, do you have any date/time column in the table? Is it possible to have that extra column anyway to see the time of a newly inserted row?
You may have to check the lastest row entered, save its field value into a variable. Then do the select based on the variable value.
Based on the vague last row id you could try the following (it's not pretty). But again, if you have date/time that's more accurate.
select attribute from table
where field = (select field from table
where rowid =(select max(rowid) from table))
;
upate
Do you have the priviledge to set up your insert command as below:
insert into table (id, col1, col2,...) values (1,'something', 'something',...)
returning id into variable; -- you may either save field or id depending on your table
Then you may use this variable to select the records you want.