support limit with offset

2026-05-24 18:51:31 +00:00 · 2025-09-04 08:44:27 -07:00
parent e030913d9f
commit 20f61388bf
6 changed files with 607 additions and 22 deletions
--- a/weed/query/engine/aggregations.go
+++ b/weed/query/engine/aggregations.go
@@ -3,6 +3,7 @@ package engine
 import (
 	"context"
 	"fmt"
+	"strconv"
 	"strings"

 	"github.com/seaweedfs/seaweedfs/weed/mq/topic"
@@ -348,6 +349,24 @@ func (e *SQLEngine) executeAggregationQuery(ctx context.Context, hybridScanner *

 // executeAggregationQueryWithPlan handles SELECT queries with aggregation functions and populates execution plan
 func (e *SQLEngine) executeAggregationQueryWithPlan(ctx context.Context, hybridScanner *HybridMessageScanner, aggregations []AggregationSpec, stmt *SelectStatement, plan *QueryExecutionPlan) (*QueryResult, error) {
+	// Parse LIMIT and OFFSET for aggregation results (do this first)
+	limit := 0
+	offset := 0
+	if stmt.Limit != nil && stmt.Limit.Rowcount != nil {
+		if limitExpr, ok := stmt.Limit.Rowcount.(*SQLVal); ok && limitExpr.Type == IntVal {
+			if limit64, err := strconv.ParseInt(string(limitExpr.Val), 10, 64); err == nil {
+				limit = int(limit64)
+			}
+		}
+	}
+	if stmt.Limit != nil && stmt.Limit.Offset != nil {
+		if offsetExpr, ok := stmt.Limit.Offset.(*SQLVal); ok && offsetExpr.Type == IntVal {
+			if offset64, err := strconv.ParseInt(string(offsetExpr.Val), 10, 64); err == nil {
+				offset = int(offset64)
+			}
+		}
+	}
+
 	// Parse WHERE clause for filtering
 	var predicate func(*schema_pb.RecordValue) bool
 	var err error
@@ -372,6 +391,29 @@ func (e *SQLEngine) executeAggregationQueryWithPlan(ctx context.Context, hybridS
 			if isDebugMode(ctx) {
 				fmt.Printf("Using fast hybrid statistics for aggregation (parquet stats + live log counts)\n")
 			}
+			
+			// Apply OFFSET and LIMIT to fast path results too
+			if offset > 0 || limit > 0 {
+				rows := fastResult.Rows
+				// Apply OFFSET first
+				if offset > 0 {
+					if offset >= len(rows) {
+						rows = [][]sqltypes.Value{}
+					} else {
+						rows = rows[offset:]
+					}
+				}
+				// Apply LIMIT after OFFSET
+				if limit >= 0 { // Handle LIMIT 0 case
+					if limit == 0 {
+						rows = [][]sqltypes.Value{}
+					} else if len(rows) > limit {
+						rows = rows[:limit]
+					}
+				}
+				fastResult.Rows = rows
+			}
+			
 			return fastResult, nil
 		}
 	}
@@ -381,11 +423,12 @@ func (e *SQLEngine) executeAggregationQueryWithPlan(ctx context.Context, hybridS
 		fmt.Printf("Using full table scan for aggregation (parquet optimization not applicable)\n")
 	}

-	// Build scan options for full table scan (aggregations need all data)
+	// Build scan options for full table scan (aggregations need all data during scanning)
 	hybridScanOptions := HybridScanOptions{
 		StartTimeNs: startTimeNs,
 		StopTimeNs:  stopTimeNs,
-		Limit:       0, // No limit for aggregations - need all data
+		Limit:       0, // No limit during scanning - need all data for aggregation
+		Offset:      0, // No offset during scanning - OFFSET applies to final results
 		Predicate:   predicate,
 	}

@@ -440,9 +483,31 @@ func (e *SQLEngine) executeAggregationQueryWithPlan(ctx context.Context, hybridS
 		row[i] = e.formatAggregationResult(spec, aggResults[i])
 	}

+	// Apply OFFSET and LIMIT to aggregation results
+	rows := [][]sqltypes.Value{row}
+	if offset > 0 || limit > 0 {
+		// Apply OFFSET first
+		if offset > 0 {
+			if offset >= len(rows) {
+				rows = [][]sqltypes.Value{}
+			} else {
+				rows = rows[offset:]
+			}
+		}
+
+		// Apply LIMIT after OFFSET
+		if limit >= 0 { // Handle LIMIT 0 case
+			if limit == 0 {
+				rows = [][]sqltypes.Value{}
+			} else if len(rows) > limit {
+				rows = rows[:limit]
+			}
+		}
+	}
+
 	return &QueryResult{
 		Columns: columns,
-		Rows:    [][]sqltypes.Value{row},
+		Rows:    rows,
 	}, nil
 }

--- a/weed/query/engine/engine.go
+++ b/weed/query/engine/engine.go
@@ -85,6 +85,7 @@ type WhereClause struct {

 type LimitClause struct {
 	Rowcount ExprNode
+	Offset   ExprNode
 }

 func (s *SelectStatement) isStatement() {}
@@ -381,19 +382,46 @@ func parseSelectStatement(sql string) (*SelectStatement, error) {
 			}
 		}

-		// Parse LIMIT clause
+		// Parse LIMIT clause with optional OFFSET
 		limitIdx := strings.Index(strings.ToUpper(remaining), "LIMIT")
 		if limitIdx != -1 {
 			limitClause := remaining[limitIdx+5:] // Skip "LIMIT"
 			limitClause = strings.TrimSpace(limitClause)

-			if _, err := strconv.Atoi(limitClause); err == nil {
-				s.Limit = &LimitClause{
+			// Check for OFFSET keyword
+			limitClauseUpper := strings.ToUpper(limitClause)
+			offsetIdx := strings.Index(limitClauseUpper, "OFFSET")
+
+			var limitValue, offsetValue string
+			if offsetIdx != -1 {
+				// Parse LIMIT N OFFSET M syntax
+				limitValue = strings.TrimSpace(limitClause[:offsetIdx])
+				offsetValue = strings.TrimSpace(limitClause[offsetIdx+6:]) // Skip "OFFSET"
+			} else {
+				// Parse LIMIT N syntax only
+				limitValue = limitClause
+			}
+
+			// Create LIMIT clause
+			if _, err := strconv.Atoi(limitValue); err == nil {
+				limitClauseStruct := &LimitClause{
 					Rowcount: &SQLVal{
 						Type: IntVal,
-						Val:  []byte(limitClause),
+						Val:  []byte(limitValue),
 					},
 				}
+
+				// Add OFFSET if present
+				if offsetValue != "" {
+					if _, err := strconv.Atoi(offsetValue); err == nil {
+						limitClauseStruct.Offset = &SQLVal{
+							Type: IntVal,
+							Val:  []byte(offsetValue),
+						}
+					}
+				}
+
+				s.Limit = limitClauseStruct
 			}
 		}
 	}
@@ -1387,8 +1415,9 @@ func (e *SQLEngine) executeSelectStatement(ctx context.Context, stmt *SelectStat
 		}
 	}

-	// Parse LIMIT clause
+	// Parse LIMIT and OFFSET clauses
 	limit := 0
+	offset := 0
 	if stmt.Limit != nil && stmt.Limit.Rowcount != nil {
 		switch limitExpr := stmt.Limit.Rowcount.(type) {
 		case *SQLVal:
@@ -1406,6 +1435,24 @@ func (e *SQLEngine) executeSelectStatement(ctx context.Context, stmt *SelectStat
 		}
 	}

+	// Parse OFFSET clause if present
+	if stmt.Limit != nil && stmt.Limit.Offset != nil {
+		switch offsetExpr := stmt.Limit.Offset.(type) {
+		case *SQLVal:
+			if offsetExpr.Type == IntVal {
+				var parseErr error
+				offset64, parseErr := strconv.ParseInt(string(offsetExpr.Val), 10, 64)
+				if parseErr != nil {
+					return &QueryResult{Error: parseErr}, parseErr
+				}
+				if offset64 > math.MaxInt32 || offset64 < 0 {
+					return &QueryResult{Error: fmt.Errorf("OFFSET value %d is out of valid range", offset64)}, fmt.Errorf("OFFSET value %d is out of valid range", offset64)
+				}
+				offset = int(offset64)
+			}
+		}
+	}
+
 	// Build hybrid scan options
 	// Extract time filters from WHERE clause to optimize scanning
 	startTimeNs, stopTimeNs := int64(0), int64(0)
@@ -1417,6 +1464,7 @@ func (e *SQLEngine) executeSelectStatement(ctx context.Context, stmt *SelectStat
 		StartTimeNs: startTimeNs, // Extracted from WHERE clause time comparisons
 		StopTimeNs:  stopTimeNs,  // Extracted from WHERE clause time comparisons
 		Limit:       limit,
+		Offset:      offset,
 		Predicate:   predicate,
 	}

@@ -1556,8 +1604,9 @@ func (e *SQLEngine) executeSelectStatementWithBrokerStats(ctx context.Context, s
 		}
 	}

-	// Parse LIMIT clause
+	// Parse LIMIT and OFFSET clauses
 	limit := 0
+	offset := 0
 	if stmt.Limit != nil && stmt.Limit.Rowcount != nil {
 		switch limitExpr := stmt.Limit.Rowcount.(type) {
 		case *SQLVal:
@@ -1575,6 +1624,24 @@ func (e *SQLEngine) executeSelectStatementWithBrokerStats(ctx context.Context, s
 		}
 	}

+	// Parse OFFSET clause if present
+	if stmt.Limit != nil && stmt.Limit.Offset != nil {
+		switch offsetExpr := stmt.Limit.Offset.(type) {
+		case *SQLVal:
+			if offsetExpr.Type == IntVal {
+				var parseErr error
+				offset64, parseErr := strconv.ParseInt(string(offsetExpr.Val), 10, 64)
+				if parseErr != nil {
+					return &QueryResult{Error: parseErr}, parseErr
+				}
+				if offset64 > math.MaxInt32 || offset64 < 0 {
+					return &QueryResult{Error: fmt.Errorf("OFFSET value %d is out of valid range", offset64)}, fmt.Errorf("OFFSET value %d is out of valid range", offset64)
+				}
+				offset = int(offset64)
+			}
+		}
+	}
+
 	// Build hybrid scan options
 	// Extract time filters from WHERE clause to optimize scanning
 	startTimeNs, stopTimeNs := int64(0), int64(0)
@@ -1586,6 +1653,7 @@ func (e *SQLEngine) executeSelectStatementWithBrokerStats(ctx context.Context, s
 		StartTimeNs: startTimeNs, // Extracted from WHERE clause time comparisons
 		StopTimeNs:  stopTimeNs,  // Extracted from WHERE clause time comparisons
 		Limit:       limit,
+		Offset:      offset,
 		Predicate:   predicate,
 	}

--- a/weed/query/engine/hybrid_message_scanner.go
+++ b/weed/query/engine/hybrid_message_scanner.go
@@ -103,6 +103,9 @@ type HybridScanOptions struct {
 	// Row limit - 0 means no limit
 	Limit int

+	// Row offset - 0 means no offset
+	Offset int
+
 	// Predicate for WHERE clause filtering
 	Predicate func(*schema_pb.RecordValue) bool
 }
@@ -222,13 +225,35 @@ func (hms *HybridMessageScanner) ScanWithStats(ctx context.Context, options Hybr
 			}
 		}

-		// Apply global limit across all partitions
-		if options.Limit > 0 && len(results) >= options.Limit {
-			results = results[:options.Limit]
+		// Apply global limit (without offset) across all partitions
+		// Note: OFFSET will be applied at the end to avoid double-application
+		if options.Limit > 0 && len(results) >= options.Limit+options.Offset {
 			break
 		}
 	}

+	// Apply final OFFSET and LIMIT processing (done once at the end)
+	if options.Offset > 0 || options.Limit >= 0 {
+		// Handle LIMIT 0 special case - return empty result immediately
+		if options.Limit == 0 {
+			results = []HybridScanResult{}
+		} else {
+			// Apply OFFSET first
+			if options.Offset > 0 {
+				if options.Offset >= len(results) {
+					results = []HybridScanResult{}
+				} else {
+					results = results[options.Offset:]
+				}
+			}
+
+			// Apply LIMIT after OFFSET
+			if options.Limit > 0 && len(results) > options.Limit {
+				results = results[:options.Limit]
+			}
+		}
+	}
+
 	return results, stats, nil
 }

@@ -331,8 +356,8 @@ func (hms *HybridMessageScanner) scanUnflushedDataWithStats(ctx context.Context,

 		results = append(results, result)

-		// Apply limit
-		if options.Limit > 0 && len(results) >= options.Limit {
+		// Apply limit (accounting for offset) - collect more data than needed
+		if options.Limit > 0 && len(results) >= options.Offset+options.Limit {
 			break
 		}
 	}
@@ -497,10 +522,7 @@ func (hms *HybridMessageScanner) scanPartitionHybridWithStats(ctx context.Contex
 	if len(results) == 0 {
 		sampleResults := hms.generateSampleHybridData(options)
 		results = append(results, sampleResults...)
-		// Apply limit to sample data as well
-		if options.Limit > 0 && len(results) > options.Limit {
-			results = results[:options.Limit]
-		}
+		// Note: OFFSET and LIMIT will be applied at the end of the main scan function
 	}

 	return results, stats, nil
@@ -930,10 +952,7 @@ func (hms *HybridMessageScanner) generateSampleHybridData(options HybridScanOpti
 		sampleData = filtered
 	}

-	// Apply limit
-	if options.Limit > 0 && len(sampleData) > options.Limit {
-		sampleData = sampleData[:options.Limit]
-	}
+	// Note: OFFSET and LIMIT will be applied at the end of the main scan function

 	return sampleData
 }
--- a/weed/query/engine/offset_test.go
+++ b/weed/query/engine/offset_test.go
@@ -0,0 +1,249 @@
+package engine
+
+import (
+	"context"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+// TestParseSQL_OFFSET_EdgeCases tests edge cases for OFFSET parsing
+func TestParseSQL_OFFSET_EdgeCases(t *testing.T) {
+	tests := []struct {
+		name     string
+		sql      string
+		wantErr  bool
+		validate func(t *testing.T, stmt Statement, err error)
+	}{
+		{
+			name:    "Valid LIMIT OFFSET with WHERE",
+			sql:     "SELECT * FROM users WHERE age > 18 LIMIT 10 OFFSET 5",
+			wantErr: false,
+			validate: func(t *testing.T, stmt Statement, err error) {
+				selectStmt := stmt.(*SelectStatement)
+				if selectStmt.Limit == nil {
+					t.Fatal("Expected LIMIT clause, got nil")
+				}
+				if selectStmt.Limit.Offset == nil {
+					t.Fatal("Expected OFFSET clause, got nil")
+				}
+				if selectStmt.Where == nil {
+					t.Fatal("Expected WHERE clause, got nil")
+				}
+			},
+		},
+		{
+			name:    "LIMIT OFFSET with mixed case",
+			sql:     "select * from users limit 5 offset 3",
+			wantErr: false,
+			validate: func(t *testing.T, stmt Statement, err error) {
+				selectStmt := stmt.(*SelectStatement)
+				offsetVal := selectStmt.Limit.Offset.(*SQLVal)
+				if string(offsetVal.Val) != "3" {
+					t.Errorf("Expected offset value '3', got '%s'", string(offsetVal.Val))
+				}
+			},
+		},
+		{
+			name:    "LIMIT OFFSET with extra spaces",
+			sql:     "SELECT * FROM users LIMIT   10   OFFSET   20  ",
+			wantErr: false,
+			validate: func(t *testing.T, stmt Statement, err error) {
+				selectStmt := stmt.(*SelectStatement)
+				limitVal := selectStmt.Limit.Rowcount.(*SQLVal)
+				offsetVal := selectStmt.Limit.Offset.(*SQLVal)
+				if string(limitVal.Val) != "10" {
+					t.Errorf("Expected limit value '10', got '%s'", string(limitVal.Val))
+				}
+				if string(offsetVal.Val) != "20" {
+					t.Errorf("Expected offset value '20', got '%s'", string(offsetVal.Val))
+				}
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			stmt, err := ParseSQL(tt.sql)
+
+			if tt.wantErr {
+				if err == nil {
+					t.Errorf("Expected error, but got none")
+				}
+				return
+			}
+
+			if err != nil {
+				t.Errorf("Unexpected error: %v", err)
+				return
+			}
+
+			if tt.validate != nil {
+				tt.validate(t, stmt, err)
+			}
+		})
+	}
+}
+
+// TestSQLEngine_OFFSET_EdgeCases tests edge cases for OFFSET execution
+func TestSQLEngine_OFFSET_EdgeCases(t *testing.T) {
+	engine := NewTestSQLEngine()
+
+	t.Run("OFFSET larger than result set", func(t *testing.T) {
+		result, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events LIMIT 5 OFFSET 100")
+		if err != nil {
+			t.Fatalf("Expected no error, got %v", err)
+		}
+		if result.Error != nil {
+			t.Fatalf("Expected no query error, got %v", result.Error)
+		}
+		// Should return empty result set
+		if len(result.Rows) != 0 {
+			t.Errorf("Expected 0 rows when OFFSET > total rows, got %d", len(result.Rows))
+		}
+	})
+
+	t.Run("OFFSET with LIMIT 0", func(t *testing.T) {
+		result, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events LIMIT 0 OFFSET 2")
+		if err != nil {
+			t.Fatalf("Expected no error, got %v", err)
+		}
+		if result.Error != nil {
+			t.Fatalf("Expected no query error, got %v", result.Error)
+		}
+		// LIMIT 0 should return no rows regardless of OFFSET
+		if len(result.Rows) != 0 {
+			t.Errorf("Expected 0 rows with LIMIT 0, got %d", len(result.Rows))
+		}
+	})
+
+	t.Run("High OFFSET with small LIMIT", func(t *testing.T) {
+		result, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events LIMIT 1 OFFSET 3")
+		if err != nil {
+			t.Fatalf("Expected no error, got %v", err)
+		}
+		if result.Error != nil {
+			t.Fatalf("Expected no query error, got %v", result.Error)
+		}
+		// With 4 sample rows, OFFSET 3 LIMIT 1 should return 1 row (the last one)
+		if len(result.Rows) != 1 {
+			t.Errorf("Expected 1 row with LIMIT 1 OFFSET 3, got %d", len(result.Rows))
+		}
+	})
+}
+
+// TestSQLEngine_OFFSET_ErrorCases tests error conditions for OFFSET
+func TestSQLEngine_OFFSET_ErrorCases(t *testing.T) {
+	engine := NewTestSQLEngine()
+
+	// Test negative OFFSET - should be caught during execution
+	t.Run("Negative OFFSET value", func(t *testing.T) {
+		// Note: This would need to be implemented as validation in the execution engine
+		// For now, we test that the parser accepts it but execution might handle it
+		_, err := ParseSQL("SELECT * FROM users LIMIT 10 OFFSET -5")
+		if err != nil {
+			t.Logf("Parser rejected negative OFFSET (this is expected): %v", err)
+		} else {
+			// Parser accepts it, execution should handle validation
+			t.Logf("Parser accepts negative OFFSET, execution should validate")
+		}
+	})
+
+	// Test very large OFFSET
+	t.Run("Very large OFFSET value", func(t *testing.T) {
+		largeOffset := "2147483647" // Max int32
+		sql := "SELECT * FROM user_events LIMIT 1 OFFSET " + largeOffset
+		result, err := engine.ExecuteSQL(context.Background(), sql)
+		if err != nil {
+			// Large OFFSET might cause parsing or execution errors
+			if strings.Contains(err.Error(), "out of valid range") {
+				t.Logf("Large OFFSET properly rejected: %v", err)
+			} else {
+				t.Errorf("Unexpected error for large OFFSET: %v", err)
+			}
+		} else if result.Error != nil {
+			if strings.Contains(result.Error.Error(), "out of valid range") {
+				t.Logf("Large OFFSET properly rejected during execution: %v", result.Error)
+			} else {
+				t.Errorf("Unexpected execution error for large OFFSET: %v", result.Error)
+			}
+		} else {
+			// Should return empty result for very large offset
+			if len(result.Rows) != 0 {
+				t.Errorf("Expected 0 rows for very large OFFSET, got %d", len(result.Rows))
+			}
+		}
+	})
+}
+
+// TestSQLEngine_OFFSET_Consistency tests that OFFSET produces consistent results
+func TestSQLEngine_OFFSET_Consistency(t *testing.T) {
+	engine := NewTestSQLEngine()
+
+	// Get all rows first
+	allResult, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events")
+	if err != nil {
+		t.Fatalf("Failed to get all rows: %v", err)
+	}
+	if allResult.Error != nil {
+		t.Fatalf("Failed to get all rows: %v", allResult.Error)
+	}
+
+	totalRows := len(allResult.Rows)
+	if totalRows == 0 {
+		t.Skip("No data available for consistency test")
+	}
+
+	// Test that OFFSET + remaining rows = total rows
+	for offset := 0; offset < totalRows; offset++ {
+		t.Run("OFFSET_"+strconv.Itoa(offset), func(t *testing.T) {
+			sql := "SELECT * FROM user_events LIMIT 100 OFFSET " + strconv.Itoa(offset)
+			result, err := engine.ExecuteSQL(context.Background(), sql)
+			if err != nil {
+				t.Fatalf("Error with OFFSET %d: %v", offset, err)
+			}
+			if result.Error != nil {
+				t.Fatalf("Query error with OFFSET %d: %v", offset, result.Error)
+			}
+
+			expectedRows := totalRows - offset
+			if len(result.Rows) != expectedRows {
+				t.Errorf("OFFSET %d: expected %d rows, got %d", offset, expectedRows, len(result.Rows))
+			}
+		})
+	}
+}
+
+// TestSQLEngine_OFFSET_WithAggregation tests OFFSET with aggregation queries
+func TestSQLEngine_OFFSET_WithAggregation(t *testing.T) {
+	engine := NewTestSQLEngine()
+
+	// Note: Aggregation queries typically return single rows, so OFFSET behavior is different
+	t.Run("COUNT with OFFSET", func(t *testing.T) {
+		result, err := engine.ExecuteSQL(context.Background(), "SELECT COUNT(*) FROM user_events LIMIT 1 OFFSET 0")
+		if err != nil {
+			t.Fatalf("Expected no error, got %v", err)
+		}
+		if result.Error != nil {
+			t.Fatalf("Expected no query error, got %v", result.Error)
+		}
+		// COUNT typically returns 1 row, so OFFSET 0 should return that row
+		if len(result.Rows) != 1 {
+			t.Errorf("Expected 1 row for COUNT with OFFSET 0, got %d", len(result.Rows))
+		}
+	})
+
+	t.Run("COUNT with OFFSET 1", func(t *testing.T) {
+		result, err := engine.ExecuteSQL(context.Background(), "SELECT COUNT(*) FROM user_events LIMIT 1 OFFSET 1")
+		if err != nil {
+			t.Fatalf("Expected no error, got %v", err)
+		}
+		if result.Error != nil {
+			t.Fatalf("Expected no query error, got %v", result.Error)
+		}
+		// COUNT returns 1 row, so OFFSET 1 should return 0 rows
+		if len(result.Rows) != 0 {
+			t.Errorf("Expected 0 rows for COUNT with OFFSET 1, got %d", len(result.Rows))
+		}
+	})
+}
--- a/weed/query/engine/query_parsing_test.go
+++ b/weed/query/engine/query_parsing_test.go
@@ -345,6 +345,11 @@ func TestParseSQL_LIMIT_Clauses(t *testing.T) {
 					t.Error("Expected LIMIT rowcount, got nil")
 				}

+				// Verify no OFFSET is set
+				if selectStmt.Limit.Offset != nil {
+					t.Error("Expected OFFSET to be nil for LIMIT-only query")
+				}
+
 				sqlVal, ok := selectStmt.Limit.Rowcount.(*SQLVal)
 				if !ok {
 					t.Errorf("Expected *SQLVal, got %T", selectStmt.Limit.Rowcount)
@@ -359,6 +364,99 @@ func TestParseSQL_LIMIT_Clauses(t *testing.T) {
 				}
 			},
 		},
+		{
+			name:    "LIMIT with OFFSET",
+			sql:     "SELECT * FROM users LIMIT 10 OFFSET 5",
+			wantErr: false,
+			validate: func(t *testing.T, stmt Statement) {
+				selectStmt := stmt.(*SelectStatement)
+				if selectStmt.Limit == nil {
+					t.Fatal("Expected LIMIT clause, got nil")
+				}
+
+				// Verify LIMIT value
+				if selectStmt.Limit.Rowcount == nil {
+					t.Error("Expected LIMIT rowcount, got nil")
+				}
+
+				limitVal, ok := selectStmt.Limit.Rowcount.(*SQLVal)
+				if !ok {
+					t.Errorf("Expected *SQLVal for LIMIT, got %T", selectStmt.Limit.Rowcount)
+				}
+
+				if limitVal.Type != IntVal {
+					t.Errorf("Expected IntVal type for LIMIT, got %d", limitVal.Type)
+				}
+
+				if string(limitVal.Val) != "10" {
+					t.Errorf("Expected limit value '10', got '%s'", string(limitVal.Val))
+				}
+
+				// Verify OFFSET value
+				if selectStmt.Limit.Offset == nil {
+					t.Fatal("Expected OFFSET clause, got nil")
+				}
+
+				offsetVal, ok := selectStmt.Limit.Offset.(*SQLVal)
+				if !ok {
+					t.Errorf("Expected *SQLVal for OFFSET, got %T", selectStmt.Limit.Offset)
+				}
+
+				if offsetVal.Type != IntVal {
+					t.Errorf("Expected IntVal type for OFFSET, got %d", offsetVal.Type)
+				}
+
+				if string(offsetVal.Val) != "5" {
+					t.Errorf("Expected offset value '5', got '%s'", string(offsetVal.Val))
+				}
+			},
+		},
+		{
+			name:    "LIMIT with OFFSET zero",
+			sql:     "SELECT * FROM users LIMIT 5 OFFSET 0",
+			wantErr: false,
+			validate: func(t *testing.T, stmt Statement) {
+				selectStmt := stmt.(*SelectStatement)
+				if selectStmt.Limit == nil {
+					t.Fatal("Expected LIMIT clause, got nil")
+				}
+
+				// Verify OFFSET is 0
+				if selectStmt.Limit.Offset == nil {
+					t.Fatal("Expected OFFSET clause, got nil")
+				}
+
+				offsetVal, ok := selectStmt.Limit.Offset.(*SQLVal)
+				if !ok {
+					t.Errorf("Expected *SQLVal for OFFSET, got %T", selectStmt.Limit.Offset)
+				}
+
+				if string(offsetVal.Val) != "0" {
+					t.Errorf("Expected offset value '0', got '%s'", string(offsetVal.Val))
+				}
+			},
+		},
+		{
+			name:    "LIMIT with large OFFSET",
+			sql:     "SELECT * FROM users LIMIT 100 OFFSET 1000",
+			wantErr: false,
+			validate: func(t *testing.T, stmt Statement) {
+				selectStmt := stmt.(*SelectStatement)
+				if selectStmt.Limit == nil {
+					t.Fatal("Expected LIMIT clause, got nil")
+				}
+
+				// Verify large OFFSET value
+				offsetVal, ok := selectStmt.Limit.Offset.(*SQLVal)
+				if !ok {
+					t.Errorf("Expected *SQLVal for OFFSET, got %T", selectStmt.Limit.Offset)
+				}
+
+				if string(offsetVal.Val) != "1000" {
+					t.Errorf("Expected offset value '1000', got '%s'", string(offsetVal.Val))
+				}
+			},
+		},
 	}

 	for _, tt := range tests {
--- a/weed/query/engine/select_test.go
+++ b/weed/query/engine/select_test.go
@@ -92,6 +92,92 @@ func TestSQLEngine_SelectFromNonExistentTable(t *testing.T) {
 	}
 }

+func TestSQLEngine_SelectWithOffset(t *testing.T) {
+	engine := NewTestSQLEngine()
+
+	// Test SELECT with OFFSET only
+	result, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events LIMIT 10 OFFSET 1")
+	if err != nil {
+		t.Fatalf("Expected no error, got %v", err)
+	}
+
+	if result.Error != nil {
+		t.Fatalf("Expected no query error, got %v", result.Error)
+	}
+
+	// Should have fewer rows than total since we skip 1 row
+	// Sample data has 4 rows, so OFFSET 1 should give us 3 rows
+	if len(result.Rows) != 3 {
+		t.Errorf("Expected 3 rows with OFFSET 1 (4 total - 1 offset), got %d", len(result.Rows))
+	}
+}
+
+func TestSQLEngine_SelectWithLimitAndOffset(t *testing.T) {
+	engine := NewTestSQLEngine()
+
+	// Test SELECT with both LIMIT and OFFSET
+	result, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events LIMIT 2 OFFSET 1")
+	if err != nil {
+		t.Fatalf("Expected no error, got %v", err)
+	}
+
+	if result.Error != nil {
+		t.Fatalf("Expected no query error, got %v", result.Error)
+	}
+
+	// Should have exactly 2 rows (skip 1, take 2)
+	if len(result.Rows) != 2 {
+		t.Errorf("Expected 2 rows with LIMIT 2 OFFSET 1, got %d", len(result.Rows))
+	}
+}
+
+func TestSQLEngine_SelectWithOffsetExceedsRows(t *testing.T) {
+	engine := NewTestSQLEngine()
+
+	// Test OFFSET that exceeds available rows
+	result, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events LIMIT 10 OFFSET 10")
+	if err != nil {
+		t.Fatalf("Expected no error, got %v", err)
+	}
+
+	if result.Error != nil {
+		t.Fatalf("Expected no query error, got %v", result.Error)
+	}
+
+	// Should have 0 rows since offset exceeds available data
+	if len(result.Rows) != 0 {
+		t.Errorf("Expected 0 rows with large OFFSET, got %d", len(result.Rows))
+	}
+}
+
+func TestSQLEngine_SelectWithOffsetZero(t *testing.T) {
+	engine := NewTestSQLEngine()
+
+	// Test OFFSET 0 (should be same as no offset)
+	result1, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events LIMIT 3")
+	if err != nil {
+		t.Fatalf("Expected no error for LIMIT query, got %v", err)
+	}
+
+	result2, err := engine.ExecuteSQL(context.Background(), "SELECT * FROM user_events LIMIT 3 OFFSET 0")
+	if err != nil {
+		t.Fatalf("Expected no error for LIMIT OFFSET query, got %v", err)
+	}
+
+	if result1.Error != nil {
+		t.Fatalf("Expected no query error for LIMIT, got %v", result1.Error)
+	}
+
+	if result2.Error != nil {
+		t.Fatalf("Expected no query error for LIMIT OFFSET, got %v", result2.Error)
+	}
+
+	// Both should return the same number of rows
+	if len(result1.Rows) != len(result2.Rows) {
+		t.Errorf("LIMIT 3 and LIMIT 3 OFFSET 0 should return same number of rows. Got %d vs %d", len(result1.Rows), len(result2.Rows))
+	}
+}
+
 func TestSQLEngine_SelectDifferentTables(t *testing.T) {
 	engine := NewTestSQLEngine()