How will you create a table with foreign key in MySQL query?

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How will you create a table with foreign key in MySQL query?

Following are the syntax of the ALTER TABLE statement to add a foreign key in the existing table:

  1. ALTER TABLE table_name.
  2. ADD [CONSTRAINT [symbol]] FOREIGN KEY.
  3. [index_name] (column_name.)
  4. REFERENCES table_name (column_name,…)
  5. ON DELETE referenceOption.
  6. ON UPDATE referenceOption.

Can you add foreign key after creating table in MySQL?

You can add foreign key constraint using CREATE TABLE or ALTER TABLE statements in SQL. Here’s the syntax to create foreign key in MySQL. ALTER TABLE table_name ADD CONSTRAINT constraint_name FOREIGN KEY (foreign_key_name,…)

How do I select a database to create a table in MySQL?

Create a Table in MySQL Shell

  1. Step 1: Log into the MySQL Shell. Open a terminal window and log into the MySQL shell. Use either an existing MySQL user account or log in as root.
  2. Step 2: Create a Database. Let’s create a movies database.
  3. Step 3: Create a Table. We’ll create a table containing information about two movies:

Can we create foreign key without primary key?

A FOREIGN KEY constraint does not have to be linked only to a PRIMARY KEY constraint in another table; it can also be defined to reference the columns of a UNIQUE constraint in another table. So in your case if you make AnotherID unique, it will be allowed.

How do I create a SQL table from another database?

SQL Server CREATE TABLE

  1. First, specify the name of the database in which the table is created.
  2. Second, specify the schema to which the new table belongs.
  3. Third, specify the name of the new table.
  4. Fourth, each table should have a primary key which consists of one or more columns.

How do you SELECT a database before creating a table?

You can specify the DB Name in the same query: CREATE TABLE database_name. table_name ( column_name1 data_type, column_name2 data_type, column_name3 data_type.. ) Also don’t forget the table schema name database_name.

How can I get data from another table?

In SQL, to fetch data from multiple tables, the join operator is used. The join operator adds or removes rows in the virtual table that is used by SQL server to process data before the other steps of the query consume the data.

Can you create SQL table without primary key?

Should you create a database table without a primary key? No. Every table should have some column (or set of columns) that uniquely identifies one and only one row. It makes it much easier to maintain the data.

Can 2 foreign keys be a primary key?

You have to have a primary key, however the two foreign keys could form a compound primary key.