What does asterisk mean in sql

The asterisk (*) in SQL is a wildcard character used to retrieve all columns in the table. It can be used to retrieve all columns or columns with a specific prefix: Retrieve all columns: SELECT * FROM table_name; Retrieve columns with a specific prefix: SELECT customer_* FROM table_name;

The meaning of the asterisk (*) in SQL

The asterisk (*) in SQL is a wildcard character used to retrieve all columns in the table. It can be used in the following two situations:

1. Retrieve all columns

Use asterisk to retrieve all columns in the table:

<code class="sql">SELECT * FROM table_name;</code>

This will return all rows for all columns in the table.

2. Retrieve columns with a specific prefix

The asterisk can also be used with a column name prefix to retrieve all columns with that prefix. For example, to retrieve all columns prefixed with "customer_", you can use the following query:

<code class="sql">SELECT customer_* FROM table_name;</code>

This will return all columns prefixed with "customer_".

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