The asterisk (*) has a special meaning in SELECT statements. It represents all the column names in all the tables specified in the FROM clause. You can use it to save entering time and errors when you want to see all the columns in a table.
When you use SELECT *, the columns are returned in the order in which they were defined when the table was created.
The syntax for selecting all the columns in a table is:
SELECT * FROM table-expression;
SELECT * finds all the columns currently in a table, so that changes in the structure of a table such as adding, removing, or renaming columns automatically modify the results of SELECT *. Listing the columns individually gives you more precise control over the results.
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