← Home ← Codex ← DEBT
Browse by Category
+ added · updated 7d
🤖 AI Guestbook — #database educational data only
| |
Last 30 days
13 pings — 2026-05-05 T 6 pings — 2026-05-06 W 54 pings — 2026-05-07 T 40 pings — 2026-05-08 F 113 pings — 2026-05-09 S 24 pings — 2026-05-10 S 4 pings — 2026-05-11 M 7 pings — 2026-05-12 T 26 pings — 2026-05-13 W 17 pings — 2026-05-14 T 51 pings — 2026-05-15 F 25 pings — 2026-05-16 S 6 pings — 2026-05-17 S 23 pings — 2026-05-18 M 14 pings — 2026-05-19 T 20 pings — 2026-05-20 W 37 pings — 2026-05-21 T 48 pings — 2026-05-22 F 148 pings — 2026-05-23 S 15 pings — 2026-05-24 S 20 pings — 2026-05-25 M 23 pings — 2026-05-26 T 47 pings — 2026-05-27 W 121 pings — 2026-05-28 T 22 pings — 2026-05-29 F 31 pings — 2026-05-30 S 25 pings — 2026-05-31 S 27 pings — 2026-06-01 M 16 pings — Yesterday T 35 pings — Today W
Amazonbot 5Perplexity 4ChatGPT 2Google 1
Perplexity 1
Amazonbot 816Perplexity 799Google 487ChatGPT 482Ahrefs 369Unknown AI 268SEMrush 204Meta AI 172Claude 147Bing 95Majestic 34Scrapy 26Qwen 6Sogou 6NotebookLM 2DuckDuckGo 1
crawler 3.5k crawler_json 361 pre-tracking 63
Tag total3.9k pings Terms pinged122 / 122 Distinct agents15
Level All Beginner Intermediate Advanced Tag: database
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Database Query Result Streaming PHP 8.0+ 🧠 2
Processing large result sets row-by-row without loading the entire dataset into memory - essential for PHP CLI scripts handling millions of rows.
1mo ago database intermediate
InnoDB vs MyISAM
InnoDB is the default MySQL storage engine supporting transactions, foreign keys, and row-level locking — MyISAM is legacy with table-level locking and no transaction support.
2mo ago database beginner
INSERT ... ON DUPLICATE KEY UPDATE PHP 5.1+
An atomic MySQL upsert — inserts a new row or updates the existing one if a unique key constraint would be violated.
2mo ago database intermediate
MySQL AUTO_INCREMENT
A column attribute that automatically assigns sequential integer IDs on INSERT — the standard primary key pattern in MySQL.
2mo ago database beginner
MySQL charset=utf8mb4 PHP 5.1+
The correct MySQL character set for full Unicode support — including emoji and supplementary characters that the older utf8 charset cannot store.
2mo ago php beginner
MySQL Connection Pooling PHP 5.1+
Reusing database connections across requests instead of opening and closing a new connection on every request.
2mo ago php intermediate
MySQL Date and Time Types
DATETIME, TIMESTAMP, DATE, TIME, and YEAR — each with different ranges, timezone handling, and storage sizes.
2mo ago database beginner
MySQL DSN (Data Source Name) PHP 5.1+
The connection string passed to PDO specifying the database driver, host, port, database name, and charset.
2mo ago php beginner
MySQL ENUM Type
A column that accepts only predefined string values — stored efficiently as integers but with significant schema change pain.
2mo ago database beginner
MySQL EXPLAIN
A MySQL query analysis command showing the execution plan — which indexes are used, how many rows are scanned, and where bottlenecks are.
2mo ago database intermediate
MySQL FULLTEXT Search
A built-in MySQL search engine supporting natural language and boolean full-text queries on TEXT and VARCHAR columns.
2mo ago database intermediate
MySQL GROUP BY and Aggregates
GROUP BY collapses rows with matching column values into one — aggregate functions (COUNT, SUM, AVG, MAX, MIN) compute values per group.
2mo ago database intermediate
Diagram: MySQL Index Types MySQL Index Types
B-tree, FULLTEXT, SPATIAL, and HASH indexes — each optimised for different query patterns.
2mo ago database intermediate
MySQL JOIN Types
INNER JOIN, LEFT JOIN, RIGHT JOIN, and CROSS JOIN — controlling which rows are included when combining tables.
2mo ago database beginner
MySQL JSON Column Type
A native JSON storage type introduced in MySQL 5.7 that validates, indexes, and queries JSON documents with dedicated functions.
2mo ago database intermediate
MySQL LIMIT and OFFSET Pagination 🧠 1
LIMIT restricts result row count; OFFSET skips rows for pagination — but OFFSET-based pagination degrades on large tables.
2mo ago database intermediate
MySQL NULL Handling
NULL in SQL represents an unknown value — it is not zero, not empty string, and comparisons with = NULL are always false.
2mo ago database beginner
MySQL Numeric Types
INT, BIGINT, DECIMAL, FLOAT, DOUBLE — the right type prevents overflow, precision loss, and money calculation bugs.
2mo ago database beginner
MySQL Query Cache (Deprecated)
A server-side cache for SELECT results removed in MySQL 8.0 — it caused severe scalability issues under concurrent writes.
2mo ago database intermediate
MySQL String Types: VARCHAR vs TEXT vs CHAR
CHAR is fixed-length, VARCHAR is variable-length up to 65,535 bytes, TEXT variants store large content — each with different indexing and storage behaviour.
2mo ago database beginner
✓ schema.org compliant