Module sql 

SQL generation utilities.

This module provides optimized SQL generation with:

• Pre-allocated string buffers
• Zero-copy placeholder generation for common cases
• Batch placeholder generation for IN clauses
• SQL template caching for common query patterns
• Static SQL keywords to avoid allocations
• Lazy SQL generation for deferred execution

Modules

keywords

Static SQL keywords to avoid repeated allocations.

templates

Pre-built SQL templates for common query patterns.

Structs

CachedSql

A cached lazy SQL that stores previously generated SQL for each database type.

FastSqlBuilder

An optimized SQL builder that uses a single String buffer.

LazySql

A lazily-generated SQL string that defers construction until needed.

SqlBuilder

A SQL builder for constructing queries.

SqlTemplateCache

A thread-safe cache for SQL templates.

Enums

AdvancedQueryCapacity

Extended capacity hints for advanced query types.

DatabaseType

Build a parameter placeholder for a given database type.

QueryCapacity

Capacity hints for different query types.

Constants

MYSQL_IN_PATTERNS

Pre-computed IN clause placeholder patterns for MySQL/SQLite. Format: “?, ?, ?, …” for common sizes (1-32 elements).

POSTGRES_PLACEHOLDERS

Pre-computed PostgreSQL placeholder strings for indices 1-256. This avoids format! calls for the most common parameter counts. Index 0 is unused (placeholders start at $1), but kept for simpler indexing. Pre-computed PostgreSQL parameter placeholders ($1-$256).

Functions

escape_identifier

Escape a string for use in SQL (for identifiers, not values).

global_sql_cache

Global SQL template cache for common query patterns.

needs_quoting

Check if an identifier needs quoting.

postgres_in_pattern

Get a pre-computed PostgreSQL IN placeholder pattern. Returns patterns like “$1, $2, $3” for count=3 starting at start_idx=1.

quote_identifier

Quote an identifier if needed.

write_postgres_in_pattern

Write PostgreSQL IN placeholders directly to a buffer.