import { type AggregateNode } from '../ast/aggregate.js';
import type { ColumnRefNode } from '../ast/column-ref.js';
import type { SQLNode } from '../ast/node.js';
import type { ParamLike } from '../types.js';
/**
 * Indicate if the input AST contains an aggregate expression.
 * The string content of verbatim nodes is analyzed to try to identify
 * unparsed aggregate functions calls within SQL strings.
 * @param root The root of the AST to search.
 * @returns Return 0 if no aggregate functions are found.
 *  Sets bit 1 if an AggregateFunction instance is found.
 *  Sets bit 2 if an aggregate embedded in verbatim text is found.
 */
export declare function isAggregateExpression(root: SQLNode): number;
/**
 * Collect all aggregate function nodes.
 * @param root The root of the AST to search.
 */
export declare function collectAggregates(root: SQLNode): AggregateNode[];
/**
 * Collect all unique column references.
 * Multiple references to the same column are de-duplicated, even if
 * they are not object-equal node instances.
 * @param root The root of the AST to search.
 */
export declare function collectColumns(root: SQLNode): ColumnRefNode[];
/**
 * Collect all unique dynamic parameter instances.
 * @param root The root of the AST to search.
 */
export declare function collectParams(root: SQLNode): ParamLike[];
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