UPDATE: Add some DATABASE functions

DAVERAGE
DCOUNT
DGET
DMAX
DMIN
DSUM

base/src/expressions/parser/static_analysis.rs

@@ -876,6 +876,13 @@ fn get_function_args_signature(kind: &Function, arg_count: usize) -> Vec<Signatu
         Function::Sheets => args_signature_scalars(arg_count, 0, 1),
         Function::Cell => args_signature_scalars(arg_count, 1, 1),
         Function::Info => args_signature_scalars(arg_count, 1, 1),
+
+        Function::Daverage => vec![Signature::Vector, Signature::Scalar, Signature::Vector],
+        Function::Dcount => vec![Signature::Vector, Signature::Scalar, Signature::Vector],
+        Function::Dget => vec![Signature::Vector, Signature::Scalar, Signature::Vector],
+        Function::Dmax => vec![Signature::Vector, Signature::Scalar, Signature::Vector],
+        Function::Dmin => vec![Signature::Vector, Signature::Scalar, Signature::Vector],
+        Function::Dsum => vec![Signature::Vector, Signature::Scalar, Signature::Vector],
     }
 }
 
@@ -1139,5 +1146,12 @@ fn static_analysis_on_function(kind: &Function, args: &[Node]) -> StaticResult {
         Function::Sheets => scalar_arguments(args),
         Function::Cell => scalar_arguments(args),
         Function::Info => scalar_arguments(args),
+
+        Function::Dget => not_implemented(args),
+        Function::Dmax => not_implemented(args),
+        Function::Dmin => not_implemented(args),
+        Function::Dcount => not_implemented(args),
+        Function::Daverage => not_implemented(args),
+        Function::Dsum => not_implemented(args),
     }
 }

base/src/functions/database.rs

@@ -0,0 +1,568 @@
+use crate::{
+    calc_result::CalcResult,
+    expressions::{parser::Node, token::Error, types::CellReferenceIndex},
+    Model,
+};
+
+use super::util::{compare_values, from_wildcard_to_regex, result_matches_regex};
+
+impl Model {
+    // =DAVERAGE(database, field, criteria)
+    pub(crate) fn fn_daverage(&mut self, args: &[Node], cell: CellReferenceIndex) -> CalcResult {
+        if args.len() != 3 {
+            return CalcResult::new_args_number_error(cell);
+        }
+
+        let (db_left, db_right) = match self.get_reference(&args[0], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let field_col = match self.resolve_db_field_column(db_left, db_right, &args[1], cell) {
+            Ok(c) => c,
+            Err(e) => return e,
+        };
+
+        let criteria = match self.get_reference(&args[2], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let mut sum = 0.0f64;
+        let mut count = 0usize;
+
+        let mut row = db_left.row + 1; // skip header
+        while row <= db_right.row {
+            if self.db_row_matches_criteria(db_left, db_right, row, criteria) {
+                let v = self.evaluate_cell(CellReferenceIndex {
+                    sheet: db_left.sheet,
+                    row,
+                    column: field_col,
+                });
+                if let CalcResult::Number(n) = v {
+                    if n.is_finite() {
+                        sum += n;
+                        count += 1;
+                    }
+                }
+            }
+            row += 1;
+        }
+
+        if count == 0 {
+            return CalcResult::Error {
+                error: Error::DIV,
+                origin: cell,
+                message: "No numeric values matched criteria".to_string(),
+            };
+        }
+
+        CalcResult::Number(sum / count as f64)
+    }
+
+    // =DCOUNT(database, field, criteria)
+    // Counts numeric entries in the field for rows that match criteria
+    pub(crate) fn fn_dcount(&mut self, args: &[Node], cell: CellReferenceIndex) -> CalcResult {
+        if args.len() != 3 {
+            return CalcResult::new_args_number_error(cell);
+        }
+
+        let (db_left, db_right) = match self.get_reference(&args[0], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let field_col = match self.resolve_db_field_column(db_left, db_right, &args[1], cell) {
+            Ok(c) => c,
+            Err(e) => return e,
+        };
+
+        let criteria = match self.get_reference(&args[2], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let mut count = 0usize;
+        let mut row = db_left.row + 1; // skip header
+        while row <= db_right.row {
+            if self.db_row_matches_criteria(db_left, db_right, row, criteria) {
+                let v = self.evaluate_cell(CellReferenceIndex {
+                    sheet: db_left.sheet,
+                    row,
+                    column: field_col,
+                });
+                if matches!(v, CalcResult::Number(_)) {
+                    count += 1;
+                }
+            }
+            row += 1;
+        }
+
+        CalcResult::Number(count as f64)
+    }
+
+    // =DGET(database, field, criteria)
+    // Returns the (single) field value for the unique matching row
+    pub(crate) fn fn_dget(&mut self, args: &[Node], cell: CellReferenceIndex) -> CalcResult {
+        if args.len() != 3 {
+            return CalcResult::new_args_number_error(cell);
+        }
+
+        let (db_left, db_right) = match self.get_reference(&args[0], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let field_col = match self.resolve_db_field_column(db_left, db_right, &args[1], cell) {
+            Ok(c) => c,
+            Err(e) => return e,
+        };
+
+        let criteria = match self.get_reference(&args[2], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let mut result: Option<CalcResult> = None;
+        let mut matches = 0usize;
+
+        let mut row = db_left.row + 1; // skip header
+        while row <= db_right.row {
+            if self.db_row_matches_criteria(db_left, db_right, row, criteria) {
+                matches += 1;
+                if matches > 1 {
+                    return CalcResult::Error {
+                        error: Error::NUM,
+                        origin: cell,
+                        message: "More than one matching record".to_string(),
+                    };
+                }
+                result = Some(self.evaluate_cell(CellReferenceIndex {
+                    sheet: db_left.sheet,
+                    row,
+                    column: field_col,
+                }));
+            }
+            row += 1;
+        }
+
+        match (matches, result) {
+            (0, _) | (_, None) => CalcResult::Error {
+                error: Error::VALUE,
+                origin: cell,
+                message: "No matching record".to_string(),
+            },
+            (_, Some(v)) => v,
+        }
+    }
+
+    // =DMAX(database, field, criteria)
+    pub(crate) fn fn_dmax(&mut self, args: &[Node], cell: CellReferenceIndex) -> CalcResult {
+        self.db_extreme(args, cell, true)
+    }
+
+    // =DMIN(database, field, criteria)
+    pub(crate) fn fn_dmin(&mut self, args: &[Node], cell: CellReferenceIndex) -> CalcResult {
+        self.db_extreme(args, cell, false)
+    }
+
+    // =DSUM(database, field, criteria)
+    pub(crate) fn fn_dsum(&mut self, args: &[Node], cell: CellReferenceIndex) -> CalcResult {
+        if args.len() != 3 {
+            return CalcResult::new_args_number_error(cell);
+        }
+
+        let (db_left, db_right) = match self.get_reference(&args[0], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let field_col = match self.resolve_db_field_column(db_left, db_right, &args[1], cell) {
+            Ok(c) => c,
+            Err(e) => return e,
+        };
+
+        let criteria = match self.get_reference(&args[2], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let mut sum = 0.0f64;
+
+        // skip header
+        let mut row = db_left.row + 1;
+        while row <= db_right.row {
+            if self.db_row_matches_criteria(db_left, db_right, row, criteria) {
+                let v = self.evaluate_cell(CellReferenceIndex {
+                    sheet: db_left.sheet,
+                    row,
+                    column: field_col,
+                });
+                if let CalcResult::Number(n) = v {
+                    if n.is_finite() {
+                        sum += n;
+                    }
+                }
+            }
+            row += 1;
+        }
+
+        CalcResult::Number(sum)
+    }
+
+    /// Resolve the "field" (2nd arg) to an absolute column index (i32) within the sheet.
+    /// Field can be a number (1-based index) or a header name (case-insensitive).
+    /// Returns the absolute column index, not a 1-based offset within the database range.
+    fn resolve_db_field_column(
+        &mut self,
+        db_left: CellReferenceIndex,
+        db_right: CellReferenceIndex,
+        field_arg: &Node,
+        cell: CellReferenceIndex,
+    ) -> Result<i32, CalcResult> {
+        // If numeric -> index
+        if let Ok(n) = self.get_number(field_arg, cell) {
+            let idx = if n < 1.0 {
+                n.ceil() as i32
+            } else {
+                n.floor() as i32
+            };
+            if idx < 1 || db_left.column + idx - 1 > db_right.column {
+                return Err(CalcResult::Error {
+                    error: Error::VALUE,
+                    origin: cell,
+                    message: "Field index out of range".to_string(),
+                });
+            }
+            return Ok(db_left.column + idx - 1);
+        }
+
+        // Otherwise treat as header name
+        let wanted = match self.get_string(field_arg, cell) {
+            Ok(s) => s.to_lowercase(),
+            Err(e) => return Err(e),
+        };
+
+        let mut col = db_left.column;
+        while col <= db_right.column {
+            let v = self.evaluate_cell(CellReferenceIndex {
+                sheet: db_left.sheet,
+                row: db_left.row,
+                column: col,
+            });
+            if let CalcResult::String(s) = v {
+                if s.to_lowercase() == wanted {
+                    return Ok(col);
+                }
+            }
+            col += 1;
+        }
+
+        Err(CalcResult::Error {
+            error: Error::VALUE,
+            origin: cell,
+            message: "Field header not found".to_string(),
+        })
+    }
+
+    /// Check whether a database row matches the criteria range.
+    /// Criteria logic: OR across criteria rows; AND across columns within a row.
+    fn db_row_matches_criteria(
+        &mut self,
+        db_left: CellReferenceIndex,
+        db_right: CellReferenceIndex,
+        row: i32,
+        criteria: (CellReferenceIndex, CellReferenceIndex),
+    ) -> bool {
+        let (c_left, c_right) = criteria;
+
+        // Read criteria headers (first row of criteria range)
+        // Map header name (lowercased) -> db column (if exists)
+        let mut crit_cols: Vec<Option<i32>> = Vec::new();
+        let mut col = c_left.column;
+        while col <= c_right.column {
+            let h = self.evaluate_cell(CellReferenceIndex {
+                sheet: c_left.sheet,
+                row: c_left.row,
+                column: col,
+            });
+            let db_col = if let CalcResult::String(s) = h {
+                let wanted = s.to_lowercase();
+                // Find corresponding DB column
+                let mut db_c = db_left.column;
+                let mut found: Option<i32> = None;
+                while db_c <= db_right.column {
+                    let hdr = self.evaluate_cell(CellReferenceIndex {
+                        sheet: db_left.sheet,
+                        row: db_left.row,
+                        column: db_c,
+                    });
+                    if let CalcResult::String(hs) = hdr {
+                        if hs.to_lowercase() == wanted {
+                            found = Some(db_c);
+                            break;
+                        }
+                    }
+                    db_c += 1;
+                }
+                found
+            } else {
+                None
+            };
+            crit_cols.push(db_col);
+            col += 1;
+        }
+
+        // If no criteria rows (only headers), everything matches
+        if c_right.row <= c_left.row {
+            return true;
+        }
+
+        // Evaluate each criteria row (OR)
+        let mut r = c_left.row + 1;
+        while r <= c_right.row {
+            // AND across columns for this criteria row
+            let mut and_ok = true;
+
+            for (offset, maybe_db_col) in crit_cols.iter().enumerate() {
+                // Criteria cell
+                let ccell = self.evaluate_cell(CellReferenceIndex {
+                    sheet: c_left.sheet,
+                    row: r,
+                    column: c_left.column + offset as i32,
+                });
+
+                // Empty criteria cell -> ignored
+                if matches!(ccell, CalcResult::EmptyCell | CalcResult::EmptyArg) {
+                    continue;
+                }
+
+                // Header without mapping -> ignore this criteria column (Excel ignores unknown headers)
+                let db_col = match maybe_db_col {
+                    Some(c) => *c,
+                    None => continue,
+                };
+
+                // Database value for this row/column
+                let db_val = self.evaluate_cell(CellReferenceIndex {
+                    sheet: db_left.sheet,
+                    row,
+                    column: db_col,
+                });
+
+                if !self.criteria_cell_matches(&db_val, &ccell) {
+                    and_ok = false;
+                    break;
+                }
+            }
+
+            if and_ok {
+                // This criteria row satisfied (OR)
+                return true;
+            }
+
+            r += 1;
+        }
+
+        // none matched
+        false
+    }
+
+    /// Implements Excel-like criteria matching for a single value.
+    /// Supports prefixes: <>, >=, <=, >, <, = ; wildcards * and ? for string equals.
+    fn criteria_cell_matches(&self, db_val: &CalcResult, crit_cell: &CalcResult) -> bool {
+        // Convert the criteria cell to a string for operator parsing if possible,
+        // otherwise fall back to equality via compare_values.
+        let crit_str_opt = match crit_cell {
+            CalcResult::String(s) => Some(s.clone()),
+            CalcResult::Number(n) => Some(n.to_string()),
+            CalcResult::Boolean(b) => Some(if *b {
+                "TRUE".to_string()
+            } else {
+                "FALSE".to_string()
+            }),
+            CalcResult::EmptyCell | CalcResult::EmptyArg => return true,
+            CalcResult::Error { .. } => return false,
+            CalcResult::Range { .. } | CalcResult::Array(_) => return false,
+        };
+
+        if crit_str_opt.is_none() {
+            return compare_values(db_val, crit_cell) == 0;
+        }
+        let mut crit = match crit_str_opt {
+            Some(s) => s.trim().to_string(),
+            None => return false,
+        };
+
+        // Detect operator prefix
+        let mut op = "="; // default equality (with wildcard semantics for strings)
+        let prefixes = ["<>", ">=", "<=", ">", "<", "="];
+        for p in prefixes.iter() {
+            if crit.starts_with(p) {
+                op = p;
+                crit = crit[p.len()..].trim().to_string();
+                break;
+            }
+        }
+
+        // Try to parse numeric RHS
+        let rhs_num = crit.parse::<f64>().ok();
+
+        match op {
+            ">" | ">=" | "<" | "<=" => {
+                if let Some(t) = rhs_num {
+                    // numeric comparison
+                    if let CalcResult::Number(n) = db_val {
+                        match op {
+                            ">" => *n > t,
+                            ">=" => *n >= t,
+                            "<" => *n < t,
+                            "<=" => *n <= t,
+                            _ => false,
+                        }
+                    } else {
+                        // For non-numbers, use compare_values with a number token to emulate Excel ordering
+                        let rhs = CalcResult::Number(t);
+                        let c = compare_values(db_val, &rhs);
+                        match op {
+                            ">" => c > 0,
+                            ">=" => c >= 0,
+                            "<" => c < 0,
+                            "<=" => c <= 0,
+                            _ => false,
+                        }
+                    }
+                } else {
+                    // string comparison (case-insensitive) using compare_values semantics
+                    let rhs = CalcResult::String(crit.to_lowercase());
+                    let lhs = match db_val {
+                        CalcResult::String(s) => CalcResult::String(s.to_lowercase()),
+                        x => x.clone(),
+                    };
+                    let c = compare_values(&lhs, &rhs);
+                    match op {
+                        ">" => c > 0,
+                        ">=" => c >= 0,
+                        "<" => c < 0,
+                        "<=" => c <= 0,
+                        _ => false,
+                    }
+                }
+            }
+            "<>" => {
+                // not equal (with wildcard semantics for strings)
+                // If rhs has wildcards and db_val is string, do regex; else use compare_values != 0
+                if let CalcResult::String(s) = db_val {
+                    if crit.contains('*') || crit.contains('?') {
+                        if let Ok(re) = from_wildcard_to_regex(&crit.to_lowercase(), true) {
+                            return !result_matches_regex(
+                                &CalcResult::String(s.to_lowercase()),
+                                &re,
+                            );
+                        }
+                    }
+                }
+                let rhs = if let Some(n) = rhs_num {
+                    CalcResult::Number(n)
+                } else {
+                    CalcResult::String(crit.to_lowercase())
+                };
+                let lhs = match db_val {
+                    CalcResult::String(s) => CalcResult::String(s.to_lowercase()),
+                    x => x.clone(),
+                };
+                compare_values(&lhs, &rhs) != 0
+            }
+            _ => {
+                // equality. For strings, support wildcards (*, ?)
+                if let Some(n) = rhs_num {
+                    // numeric equals
+                    if let CalcResult::Number(m) = db_val {
+                        (*m - n).abs() <= f64::EPSILON
+                    } else {
+                        compare_values(db_val, &CalcResult::Number(n)) == 0
+                    }
+                } else {
+                    // textual/boolean equals (case-insensitive), wildcard-enabled for strings
+                    if let CalcResult::String(s) = db_val {
+                        if crit.contains('*') || crit.contains('?') {
+                            if let Ok(re) = from_wildcard_to_regex(&crit.to_lowercase(), true) {
+                                return result_matches_regex(
+                                    &CalcResult::String(s.to_lowercase()),
+                                    &re,
+                                );
+                            }
+                        }
+                        return s.to_lowercase() == crit.to_lowercase();
+                    }
+                    // Fallback: compare_values equality
+                    compare_values(db_val, &CalcResult::String(crit.to_lowercase())) == 0
+                }
+            }
+        }
+    }
+
+    /// Shared implementation for DMAX/DMIN
+    fn db_extreme(
+        &mut self,
+        args: &[Node],
+        cell: CellReferenceIndex,
+        want_max: bool,
+    ) -> CalcResult {
+        if args.len() != 3 {
+            return CalcResult::new_args_number_error(cell);
+        }
+
+        let (db_left, db_right) = match self.get_reference(&args[0], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let field_col = match self.resolve_db_field_column(db_left, db_right, &args[1], cell) {
+            Ok(c) => c,
+            Err(e) => return e,
+        };
+
+        let criteria = match self.get_reference(&args[2], cell) {
+            Ok(r) => (r.left, r.right),
+            Err(e) => return e,
+        };
+
+        let mut best: Option<f64> = None;
+
+        let mut row = db_left.row + 1; // skip header
+        while row <= db_right.row {
+            if self.db_row_matches_criteria(db_left, db_right, row, criteria) {
+                let v = self.evaluate_cell(CellReferenceIndex {
+                    sheet: db_left.sheet,
+                    row,
+                    column: field_col,
+                });
+                if let CalcResult::Number(n) = v {
+                    if n.is_finite() {
+                        best = Some(match best {
+                            None => n,
+                            Some(cur) => {
+                                if want_max {
+                                    n.max(cur)
+                                } else {
+                                    n.min(cur)
+                                }
+                            }
+                        });
+                    }
+                }
+            }
+            row += 1;
+        }
+
+        match best {
+            Some(v) => CalcResult::Number(v),
+            None => CalcResult::Error {
+                error: Error::VALUE,
+                origin: cell,
+                message: "No numeric values matched criteria".to_string(),
+            },
+        }
+    }
+}

base/src/functions/mod.rs

@@ -8,6 +8,7 @@ use crate::{
 };
 
 pub(crate) mod binary_search;
+mod database;
 mod date_and_time;
 mod engineering;
 mod financial;
@@ -310,10 +311,18 @@ pub enum Function {
     Delta,
     Gestep,
     Subtotal,
+
+    // Database
+    Daverage,
+    Dcount,
+    Dget,
+    Dmax,
+    Dmin,
+    Dsum,
 }
 
 impl Function {
-    pub fn into_iter() -> IntoIter<Function, 256> {
+    pub fn into_iter() -> IntoIter<Function, 262> {
         [
             Function::And,
             Function::False,
@@ -571,6 +580,12 @@ impl Function {
             Function::Cell,
             Function::Info,
             Function::Sheets,
+            Function::Daverage,
+            Function::Dcount,
+            Function::Dget,
+            Function::Dmax,
+            Function::Dmin,
+            Function::Dsum,
         ]
         .into_iter()
     }
@@ -917,6 +932,13 @@ impl Function {
             "INFO" => Some(Function::Info),
             "SHEETS" | "_XLFN.SHEETS" => Some(Function::Sheets),
 
+            "DAVERAGE" => Some(Function::Daverage),
+            "DCOUNT" => Some(Function::Dcount),
+            "DGET" => Some(Function::Dget),
+            "DMAX" => Some(Function::Dmax),
+            "DMIN" => Some(Function::Dmin),
+            "DSUM" => Some(Function::Dsum),
+
             _ => None,
         }
     }
@@ -1182,6 +1204,12 @@ impl fmt::Display for Function {
             Function::Cell => write!(f, "CELL"),
             Function::Info => write!(f, "INFO"),
             Function::Sheets => write!(f, "SHEETS"),
+            Function::Daverage => write!(f, "DAVERAGE"),
+            Function::Dcount => write!(f, "DCOUNT"),
+            Function::Dget => write!(f, "DGET"),
+            Function::Dmax => write!(f, "DMAX"),
+            Function::Dmin => write!(f, "DMIN"),
+            Function::Dsum => write!(f, "DSUM"),
         }
     }
 }
@@ -1466,6 +1494,12 @@ impl Model {
             Function::Cell => self.fn_cell(args, cell),
             Function::Info => self.fn_info(args, cell),
             Function::Sheets => self.fn_sheets(args, cell),
+            Function::Daverage => self.fn_daverage(args, cell),
+            Function::Dcount => self.fn_dcount(args, cell),
+            Function::Dget => self.fn_dget(args, cell),
+            Function::Dmax => self.fn_dmax(args, cell),
+            Function::Dmin => self.fn_dmin(args, cell),
+            Function::Dsum => self.fn_dsum(args, cell),
         }
     }
 }