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@ -122,9 +122,35 @@ func (e *SelectStatement) AggregateResult(output Record) error { |
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return nil |
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} |
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func (e *SelectStatement) isPassingWhereClause(input Record) (bool, error) { |
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if e.selectAST.Where == nil { |
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return true, nil |
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} |
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value, err := e.selectAST.Where.evalNode(input) |
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if err != nil { |
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return false, err |
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} |
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b, ok := value.ToBool() |
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if !ok { |
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err = fmt.Errorf("WHERE expression did not return bool") |
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return false, err |
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} |
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return b, nil |
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} |
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// AggregateRow - aggregates the input record. Applies only to
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// aggregation queries.
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func (e *SelectStatement) AggregateRow(input Record) error { |
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ok, err := e.isPassingWhereClause(input) |
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if err != nil { |
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return err |
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} |
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if !ok { |
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return nil |
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} |
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for _, expr := range e.selectAST.Expression.Expressions { |
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err := expr.aggregateRow(input) |
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if err != nil { |
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@ -137,23 +163,13 @@ func (e *SelectStatement) AggregateRow(input Record) error { |
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// Eval - evaluates the Select statement for the given record. It
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// applies only to non-aggregation queries.
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func (e *SelectStatement) Eval(input, output Record) (Record, error) { |
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if whereExpr := e.selectAST.Where; whereExpr != nil { |
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value, err := whereExpr.evalNode(input) |
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ok, err := e.isPassingWhereClause(input) |
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if err != nil { |
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return nil, err |
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} |
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b, ok := value.ToBool() |
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if !ok { |
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err = fmt.Errorf("WHERE expression did not return bool") |
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return nil, err |
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} |
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if !b { |
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// Where clause is not satisfied by the row
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return nil, nil |
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} |
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} |
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if e.selectAST.Expression.All { |
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// Return the input record for `SELECT * FROM
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