/**
* Handle MySQL's plugin functions
* This is mostly for handling the null related functions that MySQL adds to the execution plan
*/
void InSub::handleFunc(gp_walk_info* gwip, Item_func* func)
{
if (func->functype() == Item_func::TRIG_COND_FUNC || func->functype() == Item_func::COND_OR_FUNC)
{
// purpose: remove the isnull() function from the parsetree in ptWorkStack.
// IDB handles the null semantics in the join operation
// trigcond(or_cond) is the only form we recognize for now
if (func->argument_count() > 2)
{
fGwip.fatalParseError = true;
fGwip.parseErrorText = "Unsupported item in IN subquery";
return;
}
Item_cond* cond;
if (func->functype() == Item_func::TRIG_COND_FUNC)
{
Item* item;
if (func->arguments()[0]->type() == Item::REF_ITEM)
item = (Item_ref*)(func->arguments()[0])->real_item();
else
item = func->arguments()[0];
cond = (Item_cond*)(item);
}
else
{
cond = (Item_cond*)(func);
}
if (cond->functype() == Item_func::COND_OR_FUNC)
{
// (cache=item) case. do nothing. ignore trigcond()?
if (cond->argument_list()->elements == 1)
return;
// (cache=item or isnull(item)) case. remove "or isnull()"
if (cond->argument_list()->elements == 2)
{
// don't know how to deal with this. don't think it's a fatal error either.
if (gwip->ptWorkStack.empty())
return;
ParseTree* pt = gwip->ptWorkStack.top();
if (!pt->left() || !pt->right())
return;
SimpleFilter* sf = dynamic_cast<SimpleFilter*>(pt->left()->data());
//assert (sf && sf->op()->op() == execplan::OP_ISNULL);
if (!sf || sf->op()->op() != execplan::OP_ISNULL)
return;
delete sf;
sf = dynamic_cast<SimpleFilter*>(pt->right()->data());
//idbassert(sf && sf->op()->op() == execplan::OP_EQ);
if (!sf || sf->op()->op() != execplan::OP_EQ)
return;
// set NULLMATCH for both operand. It's really a setting for the join.
// should only set NULLMATCH when the subtype is NOT_IN. for some IN subquery
// with aggregation column, MySQL inefficiently convert to:
// (cache=item or item is null) and item is not null, which is equivalent to
// cache = item. Do not set NULLMATCH for this case.
// Because we don't know IN or NOTIN yet, set candidate bit and switch to NULLMATCH
// later in handleNot function.
if (sf->lhs()->joinInfo() & JOIN_CORRELATED)
sf->lhs()->joinInfo(sf->lhs()->joinInfo() | JOIN_NULLMATCH_CANDIDATE);
if (sf->rhs()->joinInfo() & JOIN_CORRELATED)
sf->rhs()->joinInfo(sf->rhs()->joinInfo() | JOIN_NULLMATCH_CANDIDATE);
pt = pt->right();
gwip->ptWorkStack.pop();
gwip->ptWorkStack.push(pt);
}
}
else if (cond->functype() == Item_func::EQ_FUNC)
{
// not in (select const ...)
if (gwip->ptWorkStack.empty())
return;
ParseTree* pt = gwip->ptWorkStack.top();
SimpleFilter* sf = dynamic_cast<SimpleFilter*>(pt->data());
if (!sf || sf->op()->op() != execplan::OP_EQ)
return;
if (sf->lhs()->joinInfo() & JOIN_CORRELATED)
sf->lhs()->joinInfo(sf->lhs()->joinInfo() | JOIN_NULLMATCH_CANDIDATE);
if (sf->rhs()->joinInfo() & JOIN_CORRELATED)
sf->rhs()->joinInfo(sf->rhs()->joinInfo() | JOIN_NULLMATCH_CANDIDATE);
}
}
}
void PrintItemTree(Item* item, int indent)
{
#ifdef PURE_LIBRARY
BHERROR("NOT IMPLEMENTED! Depends on MySQL code.");
#else
static const char* name_of[] = {
"FIELD_ITEM", "FUNC_ITEM", "SUM_FUNC_ITEM", "STRING_ITEM", "INT_ITEM",
"REAL_ITEM", "NULL_ITEM", "VARBIN_ITEM", "COPY_STR_ITEM", "FIELD_AVG_ITEM",
"DEFAULT_VALUE_ITEM", "PROC_ITEM", "COND_ITEM", "REF_ITEM", "FIELD_STD_ITEM",
"FIELD_VARIANCE_ITEM", "INSERT_VALUE_ITEM", "SUBSELECT_ITEM", "ROW_ITEM",
"CACHE_ITEM", "TYPE_HOLDER", "PARAM_ITEM", "TRIGGER_FIELD_ITEM", "DECIMAL_ITEM",
"XPATH_NODESET", "XPATH_NODESET_CMP", "VIEW_FIXER_ITEM" };
static const char* sum_name_of[] = {
"COUNT_FUNC", "COUNT_DISTINCT_FUNC", "SUM_FUNC", "SUM_DISTINCT_FUNC", "AVG_FUNC",
"AVG_DISTINCT_FUNC", "MIN_FUNC", "MAX_FUNC", "STD_FUNC",
"VARIANCE_FUNC", "SUM_BIT_FUNC", "UDF_SUM_FUNC", "GROUP_CONCAT_FUNC" };
for(int i = 0; i <= indent; i++)
fprintf(stderr, "*");
fprintf(stderr, " ");
indent += 1;
if(!item) {
fprintf(stderr, "NULL item\n");
return;
}
const char* name;
Item::Type type = item->type();
if((int)type < sizeof(name_of)/sizeof(*name_of))
name = name_of[type];
else name = "BHFIELD_ITEM";
const char* result = "<unknown result type>";
switch (item->result_type()) {
case STRING_RESULT: result = "STRING_RESULT"; break;
case INT_RESULT: result = "INT_RESULT"; break;
case REAL_RESULT: result = "REAL_RESULT"; break;
case DECIMAL_RESULT: result = "DECIMAL_RESULT"; break;
}
fprintf(stderr, "%s %s @%p %s %s max_length=%d",
name, item->full_name(), (void*)item,
FieldType(item->field_type()), result, item->max_length);
if(item->result_type() == DECIMAL_RESULT)
fprintf(stderr, " [prec=%d,dec=%d,int=%d]",
item->decimal_precision(), (int)item->decimals, item->decimal_int_part());
switch(type) {
case Item::FUNC_ITEM: {
Item_func* func = static_cast <Item_func*> (item);
fprintf(stderr, " func_name=%s\n", func->func_name());
String str;
// GA, print function takes extra argument but do not use it in the base class.
func->print(&str,QT_ORDINARY);
fprintf(stderr, " f contents: %s\n", str.c_ptr_safe());
Item** args = func->arguments();
for(uint i = 0; i < func->argument_count(); i++)
PrintItemTree(args[i], indent);
return;
}
case Item::COND_ITEM: {
Item_cond* cond = static_cast <Item_cond*> (item);
fprintf(stderr, " func_name=%s\n", cond->func_name());
List_iterator<Item> li(*cond->argument_list());
Item* arg;
while ((arg = li++))
PrintItemTree(arg, indent);
return;
}
case Item::SUM_FUNC_ITEM: {
Item_sum* sum_func = static_cast <Item_sum*> (item);
uint index = sum_func->sum_func();
const char* sumname;
if (index >= sizeof(sum_name_of)/sizeof(*sum_name_of))
sumname = "<UNKNOWN>";
else
sumname = sum_name_of[index];
fprintf(stderr, " %s\n", sumname);
Item** args = sum_func->args;
uint args_count = sum_func->arg_count;
for(uint i=0; i < args_count; i++)
PrintItemTree(args[i], indent);
return;
}
case Item::REF_ITEM: {
Item_ref* ref = static_cast<Item_ref*> (item);
Item* real = ref->real_item();
fprintf(stderr, "\n");
if(ref != real) PrintItemTree(real, indent);
return;
}
case Item::INT_ITEM: {
Item_int_with_ref* int_ref = dynamic_cast<Item_int_with_ref*>(item);
if(!int_ref)
break;
// else item is an instance of Item_int_with_ref, not Item_int
fprintf(stderr, " [Item_int_with_ref]\n");
PrintItemTree(int_ref->real_item(), indent);
return;
}
case Item::SUBSELECT_ITEM:
Item_subselect* ss = dynamic_cast<Item_subselect*>(item);
fprintf(stderr, " subselect type %d\n", ss->substype());
String str;
// GA, print function takes extra argument but do not use it.
ss->get_unit()->print(&str, QT_ORDINARY);
fprintf(stderr, "%s\n", str.c_ptr_safe());
}
fprintf(stderr, "\n");
#endif
}
