func getMatch(node sqlparser.BoolExpr, index *Index) (planID PlanID, values interface{}) {
switch node := node.(type) {
case *sqlparser.AndExpr:
if planID, values = getMatch(node.Left, index); planID != SelectScatter {
return planID, values
}
if planID, values = getMatch(node.Right, index); planID != SelectScatter {
return planID, values
}
case *sqlparser.ParenBoolExpr:
return getMatch(node.Expr, index)
case *sqlparser.ComparisonExpr:
switch node.Operator {
case "=":
if !nameMatch(node.Left, index.Column) {
return SelectScatter, nil
}
if !sqlparser.IsValue(node.Right) {
return SelectScatter, nil
}
val, err := sqlparser.AsInterface(node.Right)
if err != nil {
return SelectScatter, nil
}
if index.Type == ShardKey {
planID = SelectSingleShardKey
} else {
planID = SelectSingleLookup
}
return planID, val
case "in":
if !nameMatch(node.Left, index.Column) {
return SelectScatter, nil
}
if !sqlparser.IsSimpleTuple(node.Right) {
return SelectScatter, nil
}
val, err := sqlparser.AsInterface(node.Right)
if err != nil {
return SelectScatter, nil
}
node.Right = sqlparser.ListArg("::_vals")
if index.Type == ShardKey {
planID = SelectMultiShardKey
} else {
planID = SelectMultiLookup
}
return planID, val
}
}
return SelectScatter, nil
}
func getMatch(node sqlparser.BoolExpr, col string) (planID PlanID, values interface{}) {
switch node := node.(type) {
case *sqlparser.AndExpr:
if planID, values = getMatch(node.Left, col); planID != SelectScatter {
return planID, values
}
if planID, values = getMatch(node.Right, col); planID != SelectScatter {
return planID, values
}
case *sqlparser.ParenBoolExpr:
return getMatch(node.Expr, col)
case *sqlparser.ComparisonExpr:
switch node.Operator {
case "=":
if !nameMatch(node.Left, col) {
return SelectScatter, nil
}
if !sqlparser.IsValue(node.Right) {
return SelectScatter, nil
}
val, err := asInterface(node.Right)
if err != nil {
return SelectScatter, nil
}
return SelectEqual, val
case "in":
if !nameMatch(node.Left, col) {
return SelectScatter, nil
}
if !sqlparser.IsSimpleTuple(node.Right) {
return SelectScatter, nil
}
val, err := asInterface(node.Right)
if err != nil {
return SelectScatter, nil
}
node.Right = sqlparser.ListArg("::" + ListVarName)
return SelectIN, val
}
}
return SelectScatter, nil
}