RC SM_Manager::DropTable(const char *relName){
string rel_name(relName);
//drop in system catalog
RM_FileScan system_scanner(system_fh, STRING, RELNAME_LENGTH, 0, EQ_OP,
(void*)relName, strlen(relName));
RC ret;
RM_Record record;
ret=system_scanner.GetNextRec(record);
if (ret==NOT_FOUND){
return NOT_FOUND;
}
RID rid;
record.GetRid(rid);
system_fh.DeleteRec(rid);
//------------------------
//drop in attribute catalog
RM_FileScan attribute_scanner(attribute_fh, STRING, RELNAME_LENGTH, 0, EQ_OP,
(void*)relName, strlen(relName));
while( (ret=attribute_scanner.GetNextRec(record)) != NOT_FOUND ){
record.GetRid(rid);
attribute_fh.DeleteRec(rid);
}
//-----------------------
return OK;
}
RC SM_Manager::DropTable(const char *relName){
string rel_name(relName);
//drop in system catalog
RM_FileScan system_scanner(system_fh, STRING, RELNAME_LENGTH, 0, EQ_OP,
(void*)relName, strlen(relName));
RC ret;
RM_Record record;
ret=system_scanner.GetNextRec(record);
if (ret==NOT_FOUND){
return NOT_FOUND;
}
RID rid;
record.GetRid(rid);
system_fh.DeleteRec(rid);
//------------------------
//drop in attribute catalog
RM_FileScan attribute_scanner(attribute_fh, STRING, RELNAME_LENGTH, 0, EQ_OP,
(void*)relName, strlen(relName));
while( (ret=attribute_scanner.GetNextRec(record)) != NOT_FOUND ){
record.GetRid(rid);
attribute_fh.DeleteRec(rid);
}
system((string("mv -f ")+db_dir+string(relName)+" "+db_dir+"dust/"+string(relName)).c_str());
RM_FileScan check_scanner(check_fh, STRING, RELNAME_LENGTH, 0, EQ_OP,
(void*)relName, strlen(relName));
while( (ret=attribute_scanner.GetNextRec(record)) != NOT_FOUND ){
Byte *mem;
record.GetRid(rid);
record.GetData(mem);
attribute_fh.DeleteRec(rid);
string CheckData=string("__checkdata__")+rel_name+(char*)(mem+RELNAME_LENGTH);
system((string("mv -f ")+db_dir+CheckData+" "+db_dir+"dust/"+CheckData).c_str());
}
attribute_fh.ForcePages();
system_fh.ForcePages();
check_fh.ForcePages();
//-----------------------
return OK;
}
void SM_Manager::DropIndex(const char *relName, const char* AttrName)
{
RM_FileScan attribute_scanner(attribute_fh, STRING, RELNAME_LENGTH, 0, EQ_OP,
(void*)relName, strlen(relName));
RC ret;
RM_Record record;
Byte *mem;
RID rid;
int mark=0;
while( (ret=attribute_scanner.GetNextRec(record)) != NOT_FOUND ){
record.GetRid(rid);
// attribute_fh.DeleteRec(rid);
record.GetData(mem);
if (GenString((char *)(mem+RELNAME_LENGTH),ATTRNAME_LENGTH)==GenString((char *)AttrName,strlen(AttrName))){
mark=*(int*)(mem+RELNAME_LENGTH+ATTRNAME_LENGTH+12);
if(mark&1) mark=mark-1;
memcpy((mem+RELNAME_LENGTH+ATTRNAME_LENGTH+12), &mark , 4);
RM_Record rec=RM_Record(mem, attribute_fh.GetRecordSize(), rid);
attribute_fh.UpdateRec(rec);
}
}
attribute_fh.ForcePages();
}
static RC PrintTable(SM_DbHandle &db, const char *tableName)
{
RC rc;
RM_FileHandle *pTable;
if ((rc = db.FindTableHandle(tableName, pTable)))
return rc;
int recordSize = pTable->header.recordSize;
vector<SM_ActiveAttr> *attributes;
if ((rc = db.AllAttributes(tableName, attributes)))
return rc;
RM_FileScan allScan;
if ((rc = allScan.OpenScan(*pTable, INT, 0, 0, 0, NO_OP, NULL)))
return rc;
RM_Record record;
int recordCount = 0;
printf("Table: %s\n", tableName);
while ((rc = allScan.GetNextRec(record)) == 0) {
RID rid;
if ((rc = record.GetRid(rid)))
return rc;
PageNum pageNum;
int slotNum;
if ((rc = rid.GetPageNum(pageNum)))
return rc;
if ((rc = rid.GetSlotNum(slotNum)))
return rc;
char *data;
if ((rc = record.GetData(data)))
return rc;
printf("RID: (%d,%d)\n", pageNum, slotNum);
vector<SM_ActiveAttr>::iterator pAttr;
int *pNullBitmap = (int *)(data + recordSize - sizeof(int));
for (pAttr = attributes->begin(); pAttr != attributes->end(); ++pAttr) {
SM_Attribute *attr = &pAttr->record;
if (*pNullBitmap & (1 << attr->number))
printf(" %s: Null\n", attr->attrName);
else if (attr->attrType == INT)
printf(" %s: %d\n", attr->attrName, *(int *)(data + attr->attrOffset));
else if (attr->attrType == FLOAT)
printf(" %s: %f\n", attr->attrName, *(float *)(data + attr->attrOffset));
else if (attr->attrType == STRING)
printf(" %s: %s\n", attr->attrName, data + attr->attrOffset);
}
printf("\n");
recordCount++;
}
if (rc != RM_ERR_EOF)
return rc;
if ((rc = allScan.CloseScan()))
return rc;
printf("\nTotal %d records.\n", recordCount);
return 0;
}
