Struct tidb_query_expr::types::RpnExpressionBuilder

pub struct RpnExpressionBuilder(Vec<RpnExpressionNode>);

Helper to build an RpnExpression.

Implementations

impl RpnExpressionBuilder

pub fn check_expr_tree_supported(c: &Expr) -> Result<()>

Checks whether the given expression definition tree is supported.

pub fn is_expr_eval_to_scalar(c: &Expr) -> Result<bool>

Gets the result type when expression tree is converted to RPN expression and evaluated. The result type will be either scalar or vector.

pub fn build_from_expr_tree(
    tree_node: Expr,
    ctx: &mut EvalContext,
    max_columns: usize
) -> Result<RpnExpression>

Builds the RPN expression node list from an expression definition tree.

pub fn new_for_test() -> Self

Creates a new builder instance.

Only used in tests. Normal logic should use build_from_expr_tree.

pub fn push_fn_call_for_test(
    self,
    func_meta: RpnFnMeta,
    args_len: usize,
    return_field_type: impl Into<FieldType>
) -> Self

Pushes a FnCall node.

pub fn push_constant_for_test(self, value: impl Into<ScalarValue>) -> Self

Pushes a Constant node. The field type will be auto inferred by choosing an arbitrary field type that matches the field type of the given value.

pub fn push_column_ref_for_test(self, offset: usize) -> Self

Pushes a ColumnRef node.

pub fn build_for_test(self) -> RpnExpression

Builds the RpnExpression.

Trait Implementations

impl AsRef<[RpnExpressionNode]> for RpnExpressionBuilder

fn as_ref(&self) -> &[RpnExpressionNode]

Performs the conversion.

impl Debug for RpnExpressionBuilder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.