Composite key as foreign key (sql)

by

Per the mySQL documentation you should be able to set up a foreign key mapping to composites, which will require you to create the multiple columns.

Add the columns and put this in your group table

FOREIGN KEY (`beggingTime`,`day`,`tutorId`) 
    REFERENCES tutorial(`beggingTime`,`day`,`tutorId`)

As Steven has alluded to in the below comments, you SHOULD try to re-architect this so that the tutorial table uses an actual primary key (even if it is just an identity surrogate key). This will allow for greater performance as SQL was built for this type of relationship, not composite.

More Related Contents:

  1. i have an error which i dont understand. can you help me? [closed]
  2. If two columns are 1 then make new column
  3. MySQL : isn’t in GROUP BY
  4. MySQL: Can’t create table (errno: 150)
  5. Restore table structure from frm and ibd files
  6. Subqueries with EXISTS vs IN – MySQL
  7. Error Dropping Database (Can’t rmdir ‘.test\’, errno: 17)
  8. #1292 – Incorrect date value: ‘0000-00-00’ [duplicate]
  9. mySQL query to search all tables within a database for a string?
  10. get first occurrence of last changed value of a column [closed]
  11. MySQL – Rows to Columns
  12. ROW_NUMBER() in MySQL
  13. multiple query same table but in different columns mysql
  14. How can I make SQL case sensitive string comparison on MySQL?
  15. How can I temporarily disable a foreign key constraint in MySQL?
  16. How to do a batch insert in MySQL
  17. Count the occurrences of DISTINCT values
  18. Creating a “Numbers Table” in MySQL
  19. MySQL Group by SUM
  20. Set NOW() as Default Value for datetime datatype?
  21. In SQL, how to select the top 2 rows for each group
  22. Mysql query to dynamically convert rows to columns on the basis of two columns
  23. SQL DELETE with JOIN another table for WHERE condition
  24. mysql trigger stored trigger is already used by statement which invoked stored trigger
  25. MySQL: How do I join same table multiple times?
  26. mysql update query with sub query
  27. Mysql: Order by like?
  28. Getting first day of the week in MySql using Week No
  29. Can’t import database through phpmyadmin file size too large
  30. SQL date format convert? [dd.mm.yy to YYYY-MM-DD]

Leave a Comment