#sqlshorts

PrecisionSQLPrecisionSQL
2026-02-04

10 % 0 Modulo By Zero Returns WHAT?!

Modulo by zero in SQL doesn't always crash! Some databases return NULL, others error. This breaks math operations! Watch the chaos!

youtube.com/watch?v=S-r3m92XI70

PrecisionSQLPrecisionSQL
2026-02-03

NULL IN (1,2,3) Is NOT What You Think!

Your brain will explode! Checking if NULL is IN a list returns something that makes NO sense. This breaks every query! Watch the chaos!

youtube.com/watch?v=5FqLSPXnieA

PrecisionSQLPrecisionSQL
2026-01-26

CHAR vs VARCHAR Comparison Returns ZERO Rows?!

STRING COMPARISON IS BROKEN! CHAR pads with spaces, VARCHAR doesn't! 'test' does NOT equal 'test '! Your WHERE clause returns ZERO rows! This breaks string matching! Watch!

youtube.com/watch?v=aE5TuRmO_PQ

PrecisionSQLPrecisionSQL
2026-01-26

TRUNCATE Can't Be Rolled Back?!

Your brain will EXPLODE! TRUNCATE looks safe but ROLLBACK won't save you! Data is PERMANENTLY DELETED even in a transaction! This broke a production database! Watch the horror!

youtube.com/watch?v=NbtNj_8Ru1o

PrecisionSQLPrecisionSQL
2026-01-24

Three-Valued Logic: AND - OR With NULL?!

SQL has THREE truth values: TRUE, FALSE, and UNKNOWN (NULL)! AND/OR with NULL creates logic that breaks everything! Watch!

youtube.com/watch?v=Dg3yabp9sa4

PrecisionSQLPrecisionSQL
2026-01-24

CHAR vs VARCHAR Padding?!

CHAR PADS with spaces! VARCHAR doesn't. LENGTH() returns different values for same string in CHAR vs VARCHAR. This padding will break comparisons!

youtube.com/watch?v=0DNOIV-lXyo

PrecisionSQLPrecisionSQL
2026-01-21

Conditional Aggregation with CASE?!

CASE inside SUM creates conditional aggregation! You can sum only certain rows based on conditions. This conditional math will transform your data!

youtube.com/watch?v=ncgl7_S0NvQ

PrecisionSQLPrecisionSQL
2026-01-20

UTF8MB4 Emoji Support EXPLODES Table From 500GB to 2TB?!

CHARACTER SET BOMB! Changed to utf8mb4 for emoji support! Table size EXPLODES 4x overnight! 500GB becomes 2.1TB! Disk fills up during ALTER! Database goes READ-ONLY! Watch this explosion!

youtube.com/watch?v=tKskvRTOkX0

PrecisionSQLPrecisionSQL
2026-01-17

GROUP BY NULLs Are Treated As ONE?!

GROUP BY treats all NULLs as the same group! Multiple NULL rows get grouped together. This breaks grouping logic! Watch now!

youtube.com/watch?v=KCBZwLbAF8Y

PrecisionSQLPrecisionSQL
2026-01-16

NULL = NULL Is FALSE In SQL?!

STOP SCROLLING! Comparing NULL to NULL in SQL returns FALSE, not TRUE! This breaks every assumption about equality. Your mind will explode! Watch now!

youtube.com/watch?v=5x89cEbWuPg

PrecisionSQLPrecisionSQL
2026-01-15

COALESCE(NULL, NULL, NULL) Returns WHAT?!

COALESCE with all NULLs returns something that defies logic! This function is supposed to return first non-NULL but what if all are NULL? Watch!

youtube.com/watch?v=85Dkogn0mPY

PrecisionSQLPrecisionSQL
2026-01-14

EXISTS vs IN With NULL Breaks Logic!

EXISTS and IN behave completely differently with NULL! One works, one doesn't. This breaks subquery logic! Watch the chaos!

youtube.com/watch?v=dwtsETOcH2Q

PrecisionSQLPrecisionSQL
2026-01-14

Index On NULL Column Does NOTHING?!

Your performance just DIED! Created an index but queries with NULL are still slow? Indexes IGNORE NULL values! Full table scan on millions of rows! Your index is USELESS! Watch the disaster!

youtube.com/watch?v=PUJ8KouC1V0

PrecisionSQLPrecisionSQL
2026-01-13

UPDATE With JOIN Corrupts Your Data?!

DATA CORRUPTION ALERT! UPDATE with JOIN can update the SAME row MULTIPLE times! $100 product gets THREE discounts applied = $51! Your prices are WRONG! Watch this disaster!

youtube.com/watch?v=tvrrPE2F7MU

PrecisionSQLPrecisionSQL
2026-01-12

Date Arithmetic with Leap Year?!

Leap years BREAK date math! February 28 + 1 day = February 29 in leap years, March 1 in non-leap years. This edge case will cause bugs!

youtube.com/watch?v=LndKlugNMrE

PrecisionSQLPrecisionSQL
2026-01-12

LAG - LEAD Default Value Trap?!

LAG and LEAD have DEFAULT values! When there's no previous/next row, they return the default. This hidden parameter will surprise you!

youtube.com/watch?v=zGKaBIgNThU

PrecisionSQLPrecisionSQL
2026-01-11

NULLIF and COALESCE Chain?!

NULLIF and COALESCE can be CHAINED! NULLIF converts to NULL, COALESCE converts from NULL. This transformation chain will surprise you!

youtube.com/watch?v=36UQvnnAo5s

PrecisionSQLPrecisionSQL
2026-01-10

Window PARTITION BY Changes Results?!

PARTITION BY creates separate windows! Each partition has its own running sum. This partitioning will change your aggregation results!

youtube.com/watch?v=OdUmjf_ZbSU

PrecisionSQLPrecisionSQL
2026-01-10

Auto-Increment IDs Have GAPS Forever?!

IDs are BROKEN! Failed INSERT consumes the auto-increment ID! User #1, skip #2, User #3! Your IDs have permanent GAPS! This breaks ID-based logic! Watch this chaos!

youtube.com/watch?v=qF3obGJL_MY

PrecisionSQLPrecisionSQL
2026-01-10

DateTime Timezone Shift Costs $2.3M In Missed Flights?!

TIMEZONE APOCALYPSE! Flight times stored WITHOUT timezone! UTC 14:00 displays as 2 PM but IS 11 AM local! 470 passengers MISSED flights in ONE day! Airlines lost $2.3M! Watch this disaster!

youtube.com/watch?v=gIurogQFeS4

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