duplicates

I have a code that gets data from Tables 1 and 2, and then inserts new rows into Table 3. My problem is that the code adds records that already exist. How can I prevent duplicate errors from being inserted, when the combination of groupid and userid in Table C already exists? INSERT INTO mdl_groups_members (groupid,userid) SELECT l.mgroup AS moodle, r.id AS mdl_user FROM moodle AS l JOIN mdl_user AS r ON l.orders_id = r.id WHERE l.mgroup > 0 Here's the table before I ran the script: id groupid userid timeadded 1 1 1 1372631339 2 4 2 1372689032 3 8 3 1373514395 4 3 4 1373514395 Here's the table

OK This is driving me nuts since a day. I am mainly an iOS guy so i dont know much about Proguard and stuff. I have made an Android app which includes both dropbox and Google Drive API. The app is working great if i deploy it on a phone thru Eclipse but I am getting a nasty error on Console when i try to export the app for apk file generation. My project.properties files was like so... # To enable ProGuard to shrink and obfuscate your code, uncomment this (available properties: sdk.dir, user.home): proguard.config=${sdk.dir}/tools/proguard/proguard-android.txt:proguard-project.txt:proguard

I have 2 arrays with objects in them such as: [{"Start": 1, "End": 2}, {"Start": 4, "End": 9}, {"Start": 12, "End": 16}, ... ] I want to merge the 2 arrays while removing duplicates. Currently, I am doing the following: array1.concat(array2); Then I am doing a nested $.each loop, but as my arrays get larger and larger, this takes O(n^2) time to execute and is not scalable. I presume there is a quicker way to do this, however, all of the examples I have found are working with strings or integers. Any recommended algorithms or methods out there to make this faster? This answer bases on the

For several days already I've been stuck with a problem in R, trying to make duplicate levels in multiple factor columns in data frame unique using a loop. This is part of a larger project. I have more than 200 SPSS data sets where the number of cases vary between 4,000 and 23,000 and the number of variables vary between 120 and 1,200 (an excerpt of one of the SPSS data sets can be found here ). The files contain both numeric and factor variables and many of the factor ones have duplicated levels. I have used read.spss from the foreign package to import them in data frames, keeping the value

I would like to copy a SQL's row into the same table. But in my table, I've a 'text' column. With this SQL: CREATE TEMPORARY TABLE produit2 ENGINE=MEMORY SELECT * FROM produit WHERE pdt_ID = 'IPSUMS'; UPDATE produit2 SET pdt_ID='ID_TEMP'; INSERT INTO produit SELECT * FROM produit2; DROP TABLE produit2; I get this error : #1163 - The used table type doesn't support BLOB/TEXT columns Here is my table : pdt_ID varchar(6) pdt_nom varchar(130) pdt_stitre varchar(255) pdt_accroche varchar(255) pdt_desc text pdt_img varchar(25) pdt_pdf varchar(10) pdt_garantie varchar(80) edit_ID varchar(7) scat_ID