Which statement is true regarding the primary key constraint in the table?
A primary key is a field in a table which uniquely identifies each row/record in a database table. Primary keys must contain unique values. A primary key column cannot have NULL values. Show A table can have only one primary key, which may consist of single or multiple fields. When multiple fields are used as a primary key, they are called a composite key. If a table has a primary key defined on any field(s), then you cannot have two records having the same value of that field(s). Note − You would use these concepts while creating database tables. Create Primary KeyHere is the syntax to define the ID attribute as a primary key in a CUSTOMERS table. CREATE TABLE CUSTOMERS( ID INT NOT NULL, NAME VARCHAR (20) NOT NULL, AGE INT NOT NULL, ADDRESS CHAR (25) , SALARY DECIMAL (18, 2), PRIMARY KEY (ID) ); To create a PRIMARY KEY constraint on the "ID" and "NAMES" columns when CUSTOMERS table already exists, use the following SQL syntax. Options CORRECT ANSWER : Primary key may contain duplicate values Enter the code shown above: (Note: If you cannot read the numbers in the above image, reload the page to generate a new one.) Which statement is true for a PRIMARY KEY constraint? Primary key defines a realtionship between two tables. A table in SQL must have a primary key associated with it to uniquely identify its records. A table in SQL is indexed by default based on its primary key. Primary key may or may not be unique but can be comprised of multiple fields. I used the CREATE TABLE AS syntax to merge several columns and encountered the same problem. Here is an AppleScript I wrote to speed the process up.
Which statement is true of a primary key constraint?Q14) Which of the following is true for a primary key? In a relational schema, there exist only one primary key and it can't take null values. So option C is the correct answer.
Which two statements are true about the primary key constraint in a table?Primary keys must contain unique values. A primary key column cannot have NULL values. A table can have only one primary key, which may consist of single or multiple fields.
Which is our correct statement about the primary key of a table?Explanation: The primary key is a single or combination of the field that identifies each record in a table uniquely. It cannot take a NULL value. A table can have only one primary key.
Which is true about the primary key Every table should have a primary key?Every table can have (but does not have to have) a primary key. The column or columns defined as the primary key ensure uniqueness in the table; no two rows can have the same key. The primary key of one table may also help to identify records in other tables, and be part of the second table's primary key.
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