Can psql's 'TABLE tablename' Shortcut Optimize 'SELECT * FROM table_name' Queries?

psql console shortcut key: use "TABLE table name" to query efficiently

The psql console provides many time-saving shortcut keys, such as "d" or "l". This article focuses on a particularly useful shortcut key that can simplify your workflow using "SELECT * FROM table name" queries.

Question:

Can we use shortcut keys in psql to optimize the commonly used "SELECT * FROM table name" query?

Answer:

Yes, in standard SQL, there is a shorthand syntax that can be used as a shortcut key for "SELECT * FROM". This syntax "TABLE table name" is for psql.

Advantages:

Using the "TABLE table name" syntax has several advantages:

• Concise query writing, no need to type "SELECT * FROM" every time.
• Improve readability and enhance code understandability, especially when dealing with complex queries.

Restrictions:

Although the "TABLE table name" syntax provides efficiency, it also has some limitations:

• Restricted clauses: This syntax only supports certain clauses, including WITH, UNION, INTERSECT, EXCEPT, ORDER BY, LIMIT, OFFSET, FETCH, and FOR locking.
• No WHERE clause: This syntax cannot use WHERE clauses and any form of aggregation.

Usage:

To use the "TABLE table name" shortcut key, simply replace the "SELECT * FROM table name" part of the query with "TABLE table name".

For example, no need to write:

SELECT * FROM users;

You can write:

TABLE users;

Conclusion:

The "TABLE table name" syntax is a valuable shortcut that can improve the efficiency of your SQL queries in psql. By taking advantage of this concise notation, you can simplify your code and streamline your workflow, especially when using specific clause combinations.

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