Neoview Query Guide (R2.3, R2.4, R2.5)

2 Query Plan Operators
Use the information in this section to understand the fields (called tokens) in the DESCRIPTION
column when you use the EXPLAIN statement and Neoview Performance Analyzer (NPA) to
review and understand query execution plans. For information about the EXPLAIN statement,
see the Neoview SQL Reference Manual. For information about the Neoview Performance Analyzer,
see Chapter 1 (page 11)
This section provides information about:
• “Operators and Description Fields” (page 18)
• “Understanding Joins” (page 24)
• “Nested Joins” (page 24)
• “Merge Joins” (page 27)
• “Hybrid Hash Joins” (page 29)
• “Ordered Joins” (page 31)
• “Insert Operators” (page 34)
• “Update Operators” (page 36)
• “Delete Operators” (page 39)
• “Scan Operators” (page 41)
• “Groupby and Sort Operators” (page 45)
• “Union Operators” (page 50)
• “Miscellaneous Operators” (page 51)
• “Operators Appearing Infrequently or Not At All” (page 53)
The operators listed here commonly appear in Neoview query execution plans:
• “CALL Operator” (page 51)
• “CURSOR_DELETE Operator” (page 39)
• “CURSOR_UPDATE Operator” (page 36)
• “ESP_EXCHANGE Operator” (page 21)
• “FILE_SCAN Operator” (page 41)
• “FILE_SCAN_UNIQUE Operator” (page 42)
• “FIRSTN Operator” (page 51)
• “HASH_GROUPBY Operator” (page 45)
• “HASH_PARTIAL_GROUPBY_LEAF Operator” (page 46)
• “HASH_PARTIAL_GROUPBY_ROOT Operator” (page 46)
• “HYBRID_HASH_ANTI_SEMI_JOIN Operator” (page 30)
• “HYBRID_HASH_JOIN Operator” (page 29)
• “HYBRID_HASH_SEMI_JOIN Operator” (page 30)
• “INDEX_SCAN Operator” (page 43)
• “INDEX_SCAN_UNIQUE Operator” (page 44)
• “INSERT Operator” (page 34)
• “INSERT_VSBB Operator” (page 35)
• “LEFT_HYBRID_HASH_JOIN Operator” (page 31)
• “LEFT_MERGE_JOIN Operator” (page 29)
• “LEFT_NESTED_JOIN Operator” (page 26)
• “LEFT_ORDERED_HASH_JOIN Operator” (page 33)
• “MERGE_ANTI_SEMI_JOIN Operator” (page 28)
• “MERGE_JOIN Operator” (page 27)
• “MERGE_SEMI_JOIN Operator” (page 28)
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