10. Which of the following key is considered unique in a table?Primary key Candidate key Foreign key Super keyAnswer: A) Primary keyExplanation:Primary key is considered unique in a table.Discuss this Question DBMS Language Multiple-Choice Questions DBMS Constraints Multiple-Choice Questions ...
The parent and the child table must use the same storage engine, and must not beTEMPORARYor partitioned tables. They can be the same table. Constraints If a foreign keys exists, each row in the child table must match a row in the parent table. Multiple child rows can match the same pa...
AND & OR operator Advance SQL SQL Constraints SQL function SQL Join SQL Alias SQL SET operation SQL Sequences SQL ViewsIntroduction to Database KeysKeys are very important part of Relational database model. They are used to establish and identify relationships between tables and also to uniquely...
all DBMS's do not implement primary keys in the same fashion and because of that, if you wanted to create a cross platform, cross application database application, you could not use primary keys, but instead would need to put a unique constraint on the table in place of the primary ...
If *PKTableNamecontains a table name,SQLForeignKeysreturns a result set that contains the primary key of the specified table and all the foreign keys that refer to it. The list of foreign keys in other tables does not include foreign keys that point to unique constraints in the specified ta...
uniqueConstraints = { @UniqueConstraint(name = "UC_FALL_KEY_QUARTAL", columnNames = { "FALL_KEY", "QUARTAL" }), }, indexes = { @Index(name = "FALLPK", columnList = "ID"), @Index(name = "IXUC_FALL_KEY_QUARTAL", columnList = "FALL_KEY, QUARTAL"), ...
Drop all constraints in Database DROP ALL USERS FROM DATABASE Drop and Create Constraint on Very Large Table Drop and recreate table in stored procedure Drop Database Error Msg 3701, Level 11, State 1, Line 1 Drop or Truncate a particular partition. DROP Table - How to force a delete of...
What are primary keys in accounting databases, and what purpose do they serve? Explain the terms primary key, candidate key, and foreign key. Give an example for each. What are the main constraints when a relational database model is being logically designed? Explain your a...
The very definition of most constraints is based on that they have to be true for every single tuple. And this inherent serialization (not the response time of classic DBMS systems) is the reason to not implement the constraints on DB level. Also: todays DBMSs only support a rather ...
OK, so we have a small parent table (BOWIE_DAD) and a much larger child table (BOWIE_KID) with all the necessary constraints in place. Note we don’t actually have a child row with a FK DAD_ID = 1. So we can potentially delete this row from the BOWIE_DAD table (where ID = 1...