SQL in a Nutshell A Desktop Quick Reference (Kevin Kline)（Z-Library）

# SQL in a Nutshell: A Desktop Quick Reference ## 【One-Line Pitch】 A practical, vendor-comparative SQL reference that documents the syntax and behavior of hundreds of SQL statements across SQL Server, Oracle, MySQL, and PostgreSQL—ideal for developers who need a concise desktop guide or are migrating between database platforms. ## 【Book Arc】 - **Opening (~0%–9%)**: Introduces the book's purpose—covering SQL as implemented across four major databases (SQL Server, Oracle, MySQL, PostgreSQL)—and explains the RDBMS model, Codd's rules, and foundational relational database concepts. - **Early (~9%–25%)**: Dives into foundational concepts: SQL99 standard datatypes, vendor-specific datatype mappings (e.g., PostgreSQL's int2 vs. ANSI smallint), and naming conventions for database objects. - **Early (~25%–34%)**: Covers SQL syntax categories, keywords vs. reserved words, and a high-level overview of the SELECT statement, including projections, selections, and joins. - **Middle (~34%–47%)**: The heart of the book—an alphabetical command reference. Each SQL statement includes a vendor support table (supported, supported with variations, supported with limitations, or not supported) followed by SQL99 syntax and vendor-specific implementations with examples. - **Middle (~47%–end)**: Continues the command reference with detailed entries for statements like ALTER TABLE, CALL, and others, showing how each vendor implements the command differently. ## 【Key Takeaways】 - **Four-vendor comparison is the core value** (Opening): The book's unique selling point is its side-by-side treatment of SQL Server, Oracle, MySQL, and PostgreSQL—making it especially useful for developers working in multi-database environments or planning migrations. - **Codd's rules define true relational databases** (Early): Twelve principles—including logical data representation in tables, uniform NULL handling, and metadata stored as regular data—provide benchmarks for designing proper relational databases. - **Datatype mappings differ significantly across vendors** (Early): Understanding that a PostgreSQL int2 equals ANSI smallint, or that Oracle's NUMBER(p,s) has precision 1–38 and scale –84 to 127, is essential for cross-platform development. - **Naming conventions improve maintainability** (Early): Use consistent, descriptive names with underscores; avoid company names, obvious prefixes like "DB_", and quoted identifiers—these practices make SQL self-documenting and easier to migrate. - **Keywords and reserved words are not the same** (Early): Keywords have current SQL significance; reserved words may gain meaning in future releases. Both should be avoided as object names to future-proof your schema. - **Read the SQL99 section first for each command** (Middle): The book's recommended approach is to read the introductory paragraph, vendor support table, and SQL99 syntax before vendor-specific details—common features are covered once under SQL99. - **Vendor implementations vary in sophistication** (Middle): Oracle's ALTER TABLE, for example, offers extensive physical storage controls (extents, partitioning, caching), while MySQL's FOREIGN KEY and CHECK clauses are empty—accepted for portability but functionally inert. ## 【Reading Tips】 - **Use the vendor support tables as your entry point**: Before reading any command's details, check the table to see which dialects support it and how—this tells you whether to skim or deep-read. - **Read SQL99 sections thoroughly, vendor sections selectively**: Common features are explained once under SQL99; vendor sections only add dialect-specific variations. Skip vendor sections for commands you don't use. - **Treat this as a reference, not a tutorial**: Skim the conceptual chapters (RDBMS principles, datatypes, naming) once, then keep the book by your desk for the command reference. - **Pay attention to the "not supported" entries**: Knowing that SQL Server lacks CALL (use EXECUTE instead) or that MySQL ignores FOREIGN KEY clauses can save hours of debugging. - **Cross-reference CREATE TABLE when reading ALTER TABLE**: The book explicitly notes that subclauses for ALTER TABLE are documented under CREATE TABLE—don't expect full coverage in every entry. ## 【Coverage Limits】 This guide covers the book's structure, conceptual foundations, and reference approach based on excerpts through the middle of the command reference. The full alphabetical command list extends well beyond the sampled entries (ALTER PROCEDURE, ALTER TABLE, CALL), and the appendix on SQL99 and vendor-specific keywords is not covered here. ##