func (e *Evaluator) caseExpr(v *ast.CaseExpr) bool {
tmp := types.NewDatum(boolToInt64(true))
target := &tmp
if v.Value != nil {
target = v.Value.GetDatum()
}
if !target.IsNull() {
for _, val := range v.WhenClauses {
cmp, err := target.CompareDatum(*val.Expr.GetDatum())
if err != nil {
e.err = errors.Trace(err)
return false
}
if cmp == 0 {
v.SetDatum(*val.Result.GetDatum())
return true
}
}
}
if v.ElseClause != nil {
v.SetDatum(*v.ElseClause.GetDatum())
} else {
v.SetNull()
}
return true
}
