/**
 * Centralized SQL Database Wrapper — PostgreSQL, MySQL, MSSQL, SQLite
 *
 * ALL SQL database access MUST go through this file.
 * NEVER create connection pools anywhere else.
 * NEVER import `pg`/`mysql2`/`mssql`/`better-sqlite3` directly in other files.
 *
 * Mirrors the MongoDB wrapper pattern (src/core/db/index.ts):
 * - Singleton pool per URI (prevents connection exhaustion)
 * - Parameterized queries ALWAYS (prevents SQL injection)
 * - Graceful shutdown with closePool()
 * - Next.js hot-reload persistence via globalThis
 *
 * Driver auto-detection from DATABASE_URL scheme:
 *   postgresql:// or postgres:// → pg
 *   mysql://                     → mysql2
 *   mssql://                     → mssql
 *   file: or sqlite:            → better-sqlite3
 *
 * Install the driver for your database:
 *   PostgreSQL: npm install pg @types/pg
 *   MySQL:      npm install mysql2
 *   MSSQL:      npm install mssql
 *   SQLite:     npm install better-sqlite3 @types/better-sqlite3
 */
export { connect, getPool, closePool, gracefulShutdown, withTransaction, } from './sql-connection.js';
export type { PoolOptions, ResultSet } from './sql-connection.js';
/**
 * Query a single row. Returns null if not found.
 * ALWAYS use parameterized queries — NEVER interpolate values.
 *
 * @example
 * const user = await queryOne<User>('SELECT * FROM users WHERE id = $1', [userId]);
 */
export declare function queryOne<T>(sql: string, params?: unknown[]): Promise<T | null>;
/**
 * Query multiple rows.
 *
 * @example
 * const users = await queryMany<User>('SELECT * FROM users WHERE role = $1 LIMIT $2', ['admin', 50]);
 */
export declare function queryMany<T>(sql: string, params?: unknown[]): Promise<T[]>;
/**
 * Count rows in a table with optional WHERE clause.
 *
 * @example
 * const total = await count('users', { role: 'admin' });
 */
export declare function count(table: string, where?: Record<string, unknown>): Promise<number>;
/**
 * Execute a raw SQL statement.
 *
 * @example
 * await execute('UPDATE users SET active = $1 WHERE last_login < $2', [false, cutoffDate]);
 */
export declare function execute(sql: string, params?: unknown[]): Promise<{
    rowCount: number;
    rows?: unknown[];
}>;
/**
 * Insert a single row into a table.
 *
 * @example
 * await insertOne('users', { email: 'a@b.com', name: 'Alice', created_at: new Date() });
 */
export declare function insertOne(table: string, data: Record<string, unknown>): Promise<{
    rowCount: number;
    rows?: unknown[];
}>;
/**
 * Insert multiple rows in a single statement.
 *
 * @example
 * await insertMany('events', [{ type: 'click', ts: new Date() }, { type: 'view', ts: new Date() }]);
 */
export declare function insertMany(table: string, rows: Record<string, unknown>[]): Promise<void>;
/**
 * Update a single row matching the WHERE clause.
 *
 * @example
 * await updateOne('users', { id: 1 }, { name: 'Bob', updated_at: new Date() });
 */
export declare function updateOne(table: string, where: Record<string, unknown>, set: Record<string, unknown>): Promise<{
    rowCount: number;
    rows?: unknown[];
}>;
/**
 * Delete a single row matching the WHERE clause.
 *
 * @example
 * await deleteOne('tokens', { token: 'abc123' });
 */
export declare function deleteOne(table: string, where: Record<string, unknown>): Promise<{
    rowCount: number;
    rows?: unknown[];
}>;
/**
 * Build a parameterized WHERE clause from a key-value object.
 * NEVER string-interpolate user input into SQL — use this instead.
 *
 * @example
 * const { clause, values } = buildWhere({ email: 'a@b.com', active: true });
 * // clause: '"email" = $1 AND "active" = $2'
 * // values: ['a@b.com', true]
 */
export declare function buildWhere(where: Record<string, unknown>, startIdx?: number): {
    clause: string;
    values: unknown[];
};
//# sourceMappingURL=sql.d.ts.map