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SQL query for finding records where count > 1

...have more than one payment per day with the same account number SELECT user_id , COUNT(*) count FROM PAYMENT GROUP BY account, user_id , date Having COUNT(*) > 1 Update If you want to only include those that have a distinct ZIP you can get a distinct set first and then perform you HAV...
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Regular expression for letters, numbers and - _

...he expression. ([a-zA-Z0-9]+[_-])* Zero or more occurrences of one or more letters or numbers followed by an underscore or dash. This causes all names that contain a dash or underscore to have letters or numbers between them. [a-zA-Z0-9]+ One or more letters or numbers. This covers all names that ...
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Is there a MySQL option/feature to track history of changes to records?

... , value , user_id , edit_time ) VALUES ( NEW.client_id, 'first_name', NEW....
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What is the difference between a stored procedure and a view?

...hen and why to use each. Say I have two tables: tbl_user, with columns: user_id, user_name, user_pw tbl_profile, with columns: profile_id, user_id, profile_description So, if I find myself querying from those tables A LOT... instead of doing the join in EVERY piece of SQL, I would define a view...
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How to implement a unique index on two columns in rails

... add_index :subscriptions, [:user_id, :content_id], unique: true share | improve this answer | follow | ...
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Rails has_and_belongs_to_many migration

... You need to add a separate join table with only a restaurant_id and user_id (no primary key), in alphabetical order. First run your migrations, then edit the generated migration file. Rails 3 rails g migration create_restaurants_users_table Rails 4: rails g migration create_restaurants...
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How to change the foreign key referential action? (behavior)

...e refers to Users table: mysql> SHOW CREATE TABLE UserDetails; : : `User_id` int(11) DEFAULT NULL, PRIMARY KEY (`Detail_id`), KEY `FK_User_id` (`User_id`), CONSTRAINT `FK_User_id` FOREIGN KEY (`User_id`) REFERENCES `Users` (`User_id`) : : First step: mysql> ALTER TABLE `UserDeta...
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Mail multipart/alternative vs multipart/mixed

...MessageInternal(service, "me", message1) def SendMessageInternal(service, user_id, message): try: message = (service.users().messages().send(userId=user_id, body=message).execute()) print 'Message Id: %s' % message['id'] return message except errors.HttpError, error:...
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What is a proper naming convention for MySQL FKs?

...d table name]_[referencing field name] Example: CREATE TABLE users( user_id int, name varchar(100) ); CREATE TABLE messages( message_id int, user_id int ); ALTER TABLE messages ADD CONSTRAINT fk_messages_users_user_id FOREIGN KEY (user_id) REFERENCES users(user_...
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Insert auto increment primary key to existing table

...mposite primary key using the following code: DROP TABLE IF EXISTS SAKAI_USER_ID_MAP; CREATE TABLE SAKAI_USER_ID_MAP ( USER_ID VARCHAR (99) NOT NULL, EID VARCHAR (255) NOT NULL, PRIMARY KEY (USER_ID) ); INSERT INTO SAKAI_USER_ID_MAP VALUES ('admin...