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Is there an elegant way to Invert a Bit value in an SQL insert Statement?

sql
bit-inversion
null-handling
performance
Alex KataevbyAlex Kataev·Aug 16, 2024
TLDR

Quick as a rabbit & simple as one plus one: use XOR operator ^ with 1 to swing bits around:

INSERT INTO galaxy (jedi_or_sith) VALUES (midiclorian_intensity ^ 1);

This elevates a humble 0(Jedi) to a mighty 1(Sith) or de-escalates a Sith back to Jedi, right in the middle of the galactic insert.

Using tilde operator for bit inversion

The tilde operator ~ is a seasoned veteran for bit inversion in SQL Server galaxy. It's a bitwise NOT operator in disguise:

INSERT INTO table_name (bit_column) SELECT ~bit_value FROM source_table;

Any 1 you encounter will bow down to a 0, and any 0 will rise up to 1. Neighborly advice, not a trick of the Jedi mind!

Null handling and non-bit columns

On the battlefield, you might stumble upon those tricky nulls. Never fear, for ISNULL is near:

INSERT INTO table_name (bit_column) SELECT ISNULL(~bit_value, default_value) FROM source_table;

Bumping into columns not of the bit data type, enlist another champion of conversion:

INSERT INTO table_name (int_column) VALUES (1 - original_int_value);

KN-0110 from 1 back to 0 and vice versa. Just remember, don't let it sneak up to 2.

Jedi's wisdom and Sith's tricks

Avoid NOT operator for bit flips; it's not your friend in this journey. Its true calling lies in logical operations. Beware of imposters like ABS; they're not here for the greater good.

Master every technique by testing them against all oddsnull values, different species, I mean, data types, etc.

Battle strategy: efficiency and performance

Sending multiple troops (bit values) into battle? Go with the efficient strategy of INSERT INTO ... SELECT paired with the tilde ~ operator:

INSERT INTO new_empire (role) SELECT ~current_role FROM old_republic;

Stormtroopers transformed into rebel fighters, and vice versa, in one swift maneuver. Efficiency, thy name is SQL.

Other galaxies, different rules

On off-world colonies like SQL Server, sometimes the binary operator 1 - bitValue does the trick, although less common.

INSERT INTO table_name (bit_column) VALUES (1 - original_bit_value);

But rules are a bit like stormtroopers: There's always a new batch, they're worth knowing about, but you usually stick with your jedis and sith lords (~ and ^).