fix(load): adjust non-strict LOAD DATA values

pkg/sql/colexec/external/external.go

@@ -891,9 +891,24 @@ func getNullFlag(nullMap map[string][]string, attr, field string) bool {
 func shouldLoadEmptyNumericAsZero(param *ExternalParam, id types.T) bool {
 	if param == nil || param.Extern == nil ||
 		param.Extern.ExternType != int32(plan.ExternType_LOAD) ||
-		(!param.ParallelLoad && !param.LoadEmptyNumericAsZero) {
+		(!param.ParallelLoad && !param.LoadEmptyNumericAsZero && !shouldApplyLoadDataNonStrictAdjustments(param)) {
 		return false
 	}
+	if !param.ParallelLoad && !param.LoadEmptyNumericAsZero {
+		return isLoadNumericAdjustedValueType(id)
+	}
+	return isLoadNumericZeroFillType(id)
+}
+
+func shouldApplyLoadDataNonStrictAdjustments(param *ExternalParam) bool {
+	return param != nil && param.Extern != nil &&
+		param.Extern.ExternType == int32(plan.ExternType_LOAD) &&
+		param.Extern.Local &&
+		param.Extern.Format == tree.CSV &&
+		!param.StrictSqlMode
+}
+
+func isLoadNumericZeroFillType(id types.T) bool {
 	switch id {
 	case types.T_bool,
 		types.T_int8, types.T_int16, types.T_int32, types.T_int64,
@@ -906,6 +921,69 @@ func shouldLoadEmptyNumericAsZero(param *ExternalParam, id types.T) bool {
 	}
 }
 
+func isLoadNumericAdjustedValueType(id types.T) bool {
+	switch id {
+	case types.T_int8, types.T_int16, types.T_int32, types.T_int64,
+		types.T_uint8, types.T_uint16, types.T_uint32, types.T_uint64,
+		types.T_float32, types.T_float64,
+		types.T_decimal64, types.T_decimal128:
+		return true
+	default:
+		return false
+	}
+}
+
+func loadDataNonStrictNumericPrefix(val string) string {
+	val = strings.TrimSpace(val)
+	if val == "" {
+		return "0"
+	}
+
+	i := 0
+	if val[i] == '+' || val[i] == '-' {
+		i++
+	}
+	digitsStart := i
+	for i < len(val) && val[i] >= '0' && val[i] <= '9' {
+		i++
+	}
+	digits := i > digitsStart
+	if i < len(val) && val[i] == '.' {
+		i++
+		fracStart := i
+		for i < len(val) && val[i] >= '0' && val[i] <= '9' {
+			i++
+		}
+		digits = digits || i > fracStart
+	}
+	if !digits {
+		return "0"
+	}
+
+	end := i
+	if i < len(val) && (val[i] == 'e' || val[i] == 'E') {
+		exp := i + 1
+		if exp < len(val) && (val[exp] == '+' || val[exp] == '-') {
+			exp++
+		}
+		expDigits := exp
+		for exp < len(val) && val[exp] >= '0' && val[exp] <= '9' {
+			exp++
+		}
+		if exp > expDigits {
+			end = exp
+		}
+	}
+	return val[:end]
+}
+
+func truncateLoadDataStringValue(val string, width int32) string {
+	if width <= 0 || utf8.RuneCountInString(val) <= int(width) {
+		return val
+	}
+	return string([]rune(val)[:width])
+}
+
 func appendLoadEmptyNumericZero(vec *vector.Vector, id types.T, asBytes bool, mp *mpool.MPool) error {
 	if asBytes {
 		return vector.AppendBytes(vec, loadZeroBytes, false, mp)
@@ -995,6 +1073,7 @@ func getColData(bat *batch.Batch, line []csvparser.Field, rowIdx int, param *Ext
 
 	field := getFieldFromLine(line, colName, param, fieldIdx)
 	id := types.T(col.Typ.Id)
+	loadDataNonStrictAdjustments := shouldApplyLoadDataNonStrictAdjustments(param)
 	trimSpace := false
 	// T_bit carries raw bytes (parsed byte-by-byte, not as text), so whitespace
 	// bytes are data and must not be trimmed (a whitespace-only bit value would
@@ -1019,6 +1098,25 @@ func getColData(bat *batch.Batch, line []csvparser.Field, rowIdx int, param *Ext
 		return nil
 	}
 
+	zeroDateAdjusted := false
+	if loadDataNonStrictAdjustments {
+		switch {
+		case isLoadNumericAdjustedValueType(id):
+			if !field.HasStringQuote {
+				field.Val = loadDataNonStrictNumericPrefix(field.Val)
+			}
+		case id == types.T_date:
+			if _, err := types.ParseDateCast(field.Val); err != nil {
+				zeroDateAdjusted = true
+				if param.ParallelLoad {
+					field.Val = "0000-00-00"
+				}
+			}
+		case id == types.T_char || id == types.T_varchar:
+			field.Val = truncateLoadDataStringValue(field.Val, col.Typ.Width)
+		}
+	}
+
 	// In strict SQL mode (non-LOCAL load), an over-width CHAR/VARCHAR value is
 	// rejected instead of silently truncated, matching strict assignment casts
 	// (cast_strict) and MySQL's "Data too long" behavior. Uses rune count, like
@@ -1326,10 +1424,16 @@ func getColData(bat *batch.Batch, line []csvparser.Field, rowIdx int, param *Ext
 			return err
 		}
 	case types.T_date:
-		d, err := types.ParseDateCast(field.Val)
-		if err != nil {
-			logutil.Errorf("parse field[%v] err:%v", field.Val, err)
-			return moerr.NewInternalErrorf(param.Ctx, "the input value '%v' is not Date type for column %d", field.Val, colIdx)
+		var d types.Date
+		if zeroDateAdjusted {
+			d = types.Date(0)
+		} else {
+			var err error
+			d, err = types.ParseDateCast(field.Val)
+			if err != nil {
+				logutil.Errorf("parse field[%v] err:%v", field.Val, err)
+				return moerr.NewInternalErrorf(param.Ctx, "the input value '%v' is not Date type for column %d", field.Val, colIdx)
+			}
 		}
 
 		if err := vector.AppendFixed(vec, d, false, mp); err != nil {