Table::~Table()
{
RecordPage page;
page.pageIndex = 1;
page.tableName = TableName;
bm.readPage(page);
page.writenext(head);
bm.writePage(page);
}
void Table::deleteTuple(PageIndexType index)
{
RecordPage page;
page.pageIndex = index;
page.tableName = TableName;
bm.readPage(page);
PageIndexType next = page.readnext();
PageIndexType before = page.readbefore();
if (before == 1) {
head = next;
}
if(next == UNDEFINEED_PAGE_NUM)
{
RecordPage beforepage;
beforepage.pageIndex = before;
beforepage.tableName = TableName;
bm.readPage(beforepage);
beforepage.writenext(UNDEFINEED_PAGE_NUM);
bm.writePage(beforepage);
}
else
{
RecordPage nextpage;
nextpage.pageIndex = next;
nextpage.tableName = TableName;
bm.readPage(nextpage);
RecordPage beforepage;
beforepage.pageIndex = before;
beforepage.tableName = TableName;
bm.readPage(beforepage);
beforepage.writenext(nextpage.pageIndex);
nextpage.writebefore(beforepage.pageIndex);
bm.writePage(beforepage);
bm.writePage(nextpage);
}
bm.deallocatePage(page);
}
void CatalogManager::insertTable(TableInfo table)
{
CatalogPage page;
BufferManager buffer;
int i,j;
string s;
if (tableExisted(table.tableName))
{
printf("Failed to create table %s. Table already existed.\n",table.tableName.c_str());
return;
}
for (i=0; i<table.attrNum-1; i++)
for (j=i+1; j<table.attrNum; j++)
if (table.attrName[i]==table.attrName[j])
{
printf("Failed to create table %s. Attributes with the same name have been found.\n",table.tableName.c_str());
return;
}
if (table.primaryKey=="")
table.primaryKeyLoc=-1;
else
{
for (i=0; i<table.attrNum; i++)
if (table.attrName[i]==table.primaryKey)
{
table.primaryKeyLoc=i;
table.attrUnique[i]='Y';
}
}
page.tableName = table.tableName;
page.pageData[0] = (char)table.attrNum;
page.pageData[1] = (char)table.primaryKeyLoc;
for (i=0; i<table.attrNum; i++)
{
page.writeAttr(i*100+2, table.attrName[i]);
page.writeAttr(i*100+22, table.attrType[i]);
// page.writeAttr(i*100+42, table.attrIndex[i]);
page.pageData[i*100+62] = table.attrUnique[i];
*(int*)(page.pageData+(i*100+82)) = 0; //该属性上的索引总数，初始为0
}
buffer.writePage(page);
printf("Created table %s successfully!\n",table.tableName.c_str());
if (table.primaryKeyLoc>=0)
{
printf("Trying to build index on primary key automatelly...\n");
insertIndex(table.tableName, table.attrName[table.primaryKeyLoc], table.tableName+table.attrName[table.primaryKeyLoc]);
}
}
void CatalogManager::dropTable(string tableName)
{
if (!tableExisted(tableName))
{
printf("Table does not exist!\n");
}
else
{
BufferManager buffer;
IndexCatalogPage indexPage;
int n,nn,i,x,k;
string s, attrName;
indexPage.pageIndex=1;
buffer.readPage(indexPage);
n=*(int*)indexPage.pageData;
nn=n;
i=1;
k=0;
while (i<=n) //开始逐条检查，删除这张表上所有的索引
{
x=indexPage.readPrevDel(i);
if (x==0) //如果当前条未被删除
{
s=indexPage.readTableName(i);
if (s==tableName) //如果是这张表的索引，删掉
{
k++; //k用来记录删除了多少条索引
indexPage.deleteIndex(i);
attrName=indexPage.readAttrName(i);
BufferManager bm;
string filePath=bm.indexFilePath(tableName, attrName);
if (bm.indexFileIsExist(tableName, attrName))
bm.deleteIndexFile(tableName, attrName);
}
}
else //如果当前条已被删除，则最后一条位置后移
n++;
i++;
}
indexPage.pageIndex=1; //记录索引信息首页的索引总数也需要改
buffer.readPage(indexPage);
*(int*)indexPage.pageData=nn-k;
buffer.writePage(indexPage);
buffer.deleteTableCatalogFile(tableName); //删除当前表的文件
buffer.deleteTableFile(tableName); //删除当前表的record文件
printf("Dropped table %s successfully!\n",tableName.c_str());
}
}
PageIndexType Table::insertTuple(vector<Attribute> list)
{
Tuple tuple;
tuple.list = list;
tuple.createPage(TableName);
tuple.page.writebefore(1);
tuple.page.writenext(head);
if(head != UNDEFINEED_PAGE_NUM)
{
RecordPage page;
page.pageIndex = head;
page.tableName = TableName;
bm.readPage(page);
page.writebefore(tuple.page.pageIndex);
bm.writePage(page);
}
head = tuple.page.pageIndex;
tuple.convertToRawData();
bm.writePage(tuple.page);
return tuple.page.pageIndex;
}
bool CatalogManager::insertIndex(string tableName, string attrName, string indexName)
{
IndexCatalogPage indexPage;
if (indexExisted(indexName))
{
printf("Failed to insert index %s. Index name already existed!\n", indexName.c_str());
return 0;
}
else
if (!tableExisted(tableName))
{
printf("Failed to insert index %s. Table %s does not exist!\n", indexName.c_str(),tableName.c_str());
return 0;
}
else
if (!attrExisted(tableName, attrName))
{
printf("Failed to insert index %s. Attribute %s on Table %s does not exist!\n", indexName.c_str(), attrName.c_str(),tableName.c_str());
return 0;
}
else
if (!attrUnique(tableName, attrName))
{
printf("Failed to insert index %s. Attribute %s on Table %s is not unique!\n", indexName.c_str(), attrName.c_str(),tableName.c_str());
return 0;
}
else
{
indexPage.writeIndex(tableName, attrName, indexName);
BufferManager buffer;
CatalogPage catalog;
int num,i;
catalog.tableName = tableName;
buffer.readPage(catalog);
num = (int)catalog.pageData[0];
for (i=0; i<num; i++)
if (catalog.readAttrName(i) == attrName)
{
catalog.modifyAttrIndexNum(i,1);
buffer.writePage(catalog);
break;
}
printf("Inserted index %s(Attribute %s on Table %s) successfully!\n", indexName.c_str(), attrName.c_str(),tableName.c_str());
return 1;
}
}
void BPTreeNode::writeNodeRawData() {
BufferManager bufferManager;
bufferManager.writePage(nodePage);
}
void CatalogManager::deleteIndex(string indexName)
{
if (!indexExisted(indexName)) //如果没有这个索引
{
printf("Failed to delete index %s. Index does not existed.\n", indexName.c_str());
return;
}
else //有这个索引
{
BufferManager buffer;
CatalogPage catalog;
IndexCatalogPage indexPage;
string s,tableName,attrName;
int i,num,n,x;
s=indexLocation(indexName); //找到这个索引
tableName=""; //分割字符串
attrName="";
i=0;
while (s[i]!=' ')
{
tableName=tableName+s[i];
i++;
}
while (s[i]==' ')
i++;
while (s[i]!=0)
{
attrName=attrName+s[i];
i++;
}
printf("#%s# @%s@ *%s*\n",indexName.c_str(), tableName.c_str(), attrName.c_str());
printf("~%s~\n",primaryKey(tableName).c_str());
if (indexName == tableName+attrName && primaryKey(tableName) == attrName)
{
printf("Failed to delete index %s. Default index on primary key cannot be deleted.\n",indexName.c_str());
return;
}
indexPage.pageIndex=1;
buffer.readPage(indexPage);
n=*(int*)indexPage.pageData;
i=1;
while (i<=n) //开始在indexCatalogPage里逐条检查，删除这个索引
{
x=indexPage.readPrevDel(i);
if (x==0) //如果当前条未被删除
{
s=indexPage.readIndexName(i);
if (s==indexName) //如果找到要删的这条索引
{
indexPage.deleteIndex(i); //删掉它
break;
}
}
else //如果当前条已被删除，则最后一条位置后移
n++;
i++;
}
buffer.writePage(indexPage);
catalog.tableName = tableName; //在catalogPage里面的对应属性上修改索引总数
buffer.readPage(catalog);
num = (int)catalog.pageData[0];
for (i=0; i<num; i++) {
if (catalog.readAttrName(i) == attrName)
{
catalog.modifyAttrIndexNum(i,-1);
buffer.writePage(catalog);
if (catalog.readAttrIndexNum(i)==0)
{
BufferManager bm;
string filePath=bm.indexFilePath(tableName, attrName);
if (bm.indexFileIsExist(tableName, attrName))
bm.deleteIndexFile(tableName, attrName);
}
break;
}
}
printf("Deleted index %s successfully!\n",indexName.c_str());
}
}
