/**
* Drops the specified user-defined view or table from this Database object.
*
* <p>The process of dropping a table or view includes:
*
* <OL>
* <LI>checking that the specified Session's currently connected User has the right to perform
* this operation and refusing to proceed if not by throwing.
* <LI>checking for referential constraints that conflict with this operation and refusing to
* proceed if they exist by throwing.
* <LI>removing the specified Table from this Database object.
* <LI>removing any exported foreign keys Constraint objects held by any tables referenced by
* the table to be dropped. This is especially important so that the dropped Table ceases to
* be referenced, eventually allowing its full garbage collection.
* <LI>
* </OL>
*
* <p>
*
* @param name of the table or view to drop
* @param ifExists if true and if the Table to drop does not exist, fail silently, else throw
* @param isView true if the name argument refers to a View
* @param session the connected context in which to perform this operation
* @throws HsqlException if any of the checks listed above fail
*/
void dropTable(Session session, String name, boolean ifExists, boolean isView)
throws HsqlException {
Table toDrop = null;
int dropIndex = -1;
for (int i = 0; i < tTable.size(); i++) {
toDrop = (Table) tTable.get(i);
if (toDrop.equals(session, name) && isView == toDrop.isView()) {
dropIndex = i;
break;
} else {
toDrop = null;
}
}
if (dropIndex == -1) {
if (ifExists) {
return;
} else {
throw Trace.error(isView ? Trace.VIEW_NOT_FOUND : Trace.TABLE_NOT_FOUND, name);
}
}
if (!toDrop.isTemp()) {
session.checkDDLWrite();
}
if (isView) {
checkViewIsInView((View) toDrop);
} else {
checkTableIsReferenced(toDrop);
checkTableIsInView(toDrop.tableName.name);
}
tTable.remove(dropIndex);
removeExportedKeys(toDrop);
userManager.removeDbObject(toDrop.getName());
triggerNameList.removeOwner(toDrop.tableName);
indexNameList.removeOwner(toDrop.tableName);
constraintNameList.removeOwner(toDrop.tableName);
toDrop.dropTriggers();
toDrop.drop();
session.setScripting(!toDrop.isTemp());
session.commit();
}
public Result execute(Session session) {
Result result;
if (targetTable != null && session.isReadOnly() && !targetTable.isTemp()) {
HsqlException e = Error.error(ErrorCode.X_25006);
return Result.newErrorResult(e);
}
if (isExplain) {
return getExplainResult(session);
}
try {
if (subqueries.length > 0) {
materializeSubQueries(session);
}
result = getResult(session);
} catch (Throwable t) {
result = Result.newErrorResult(t, null);
result.getException().setStatementType(group, type);
}
session.sessionContext.clearStructures(this);
return result;
}
/**
* Drops the index with the specified name from this database.
*
* @param indexname the name of the index to drop
* @param ifExists if true and if the Index to drop does not exist, fail silently, else throw
* @param session the execution context
* @throws HsqlException if the index does not exist, the session lacks the permission or the
* operation violates database integrity
*/
void dropIndex(Session session, String indexname, String tableName, boolean ifExists)
throws HsqlException {
Table t = findUserTableForIndex(session, indexname);
if (t == null) {
if (ifExists) {
return;
} else {
throw Trace.error(Trace.INDEX_NOT_FOUND, indexname);
}
}
if (tableName != null && !t.getName().name.equals(tableName)) {
throw Trace.error(Trace.INDEX_NOT_FOUND, indexname);
}
t.checkDropIndex(indexname, null);
// fredt@users 20020405 - patch 1.7.0 by fredt - drop index bug
// see Table.moveDefinition();
session.commit();
session.setScripting(!t.isTemp());
TableWorks tw = new TableWorks(session, t);
tw.dropIndex(indexname);
}
/** Drops a trigger with the specified name in the given context. */
void dropTrigger(Session session, String name) throws HsqlException {
boolean found = triggerNameList.containsName(name);
Trace.check(found, Trace.TRIGGER_NOT_FOUND, name);
HsqlName tableName = (HsqlName) triggerNameList.removeName(name);
Table t = this.findUserTable(session, tableName.name);
t.dropTrigger(name);
session.setScripting(!t.isTemp());
}
/** Drops from this Database any temporary tables owned by the specified Session. */
void dropTempTables(Session ownerSession) {
int i = tTable.size();
while (i-- > 0) {
Table toDrop = (Table) tTable.get(i);
if (toDrop.isTemp() && toDrop.getOwnerSessionId() != ownerSession.getId()) {
tTable.remove(i);
}
}
}
Result getWriteAccessResult(Session session) {
try {
if (targetTable != null && !targetTable.isTemp()) {
session.checkReadWrite();
}
} catch (HsqlException e) {
return Result.newErrorResult(e);
}
return null;
}
/**
* Drops the index with the specified name from this database.
*
* @param indexname the name of the index to drop
* @param session the execution context
* @throws SQLException if the index does not exist, the session lacks the permission or the
* operation violates database integrity
*/
void dropIndex(String indexname, Session session) throws SQLException {
Table t = findUserTableForIndex(indexname, session);
if (t == null) {
throw Trace.error(Trace.INDEX_NOT_FOUND, indexname);
}
t.checkDropIndex(indexname, null);
// fredt@users 20020405 - patch 1.7.0 by fredt - drop index bug
// see Table.moveDefinition();
session.commit();
session.setScripting(!t.isTemp());
TableWorks tw = new TableWorks(t);
tw.dropIndex(indexname);
}
// this fk references -> other : other read lock
void collectTableNamesForRead(OrderedHashSet set) {
for (int i = 0; i < rangeVariables.length; i++) {
Table rangeTable = rangeVariables[i].rangeTable;
HsqlName name = rangeTable.getName();
if (rangeTable.isReadOnly() || rangeTable.isTemp()) {
continue;
}
if (name.schema == SqlInvariants.SYSTEM_SCHEMA_HSQLNAME) {
continue;
}
set.add(name);
}
for (int i = 0; i < subqueries.length; i++) {
if (subqueries[i].queryExpression != null) {
subqueries[i].queryExpression.getBaseTableNames(set);
}
}
}
/**
* Method declaration
*
* @param db
* @param file
* @param full
* @param session
* @throws SQLException
*/
static void scriptToFile(Database db, String file, boolean full, Session session)
throws SQLException {
if ((new File(file)).exists()) {
// there must be no such file; overwriting not allowed for security
throw Trace.error(Trace.FILE_IO_ERROR, file);
}
try {
long time = 0;
if (Trace.TRACE) {
time = System.currentTimeMillis();
}
// only ddl commands; needs not so much memory
Result r;
if (full) {
// no drop, no insert, and no positions for cached tables
r = db.getScript(false, false, false, session);
} else {
// no drop, no insert, but positions for cached tables
r = db.getScript(false, false, true, session);
}
Record n = r.rRoot;
FileWriter w = new FileWriter(file);
while (n != null) {
writeLine(w, (String) n.data[0]);
n = n.next;
}
// inserts are done separetely to save memory
HsqlArrayList tables = db.getTables();
for (int i = 0; i < tables.size(); i++) {
Table t = (Table) tables.get(i);
// cached tables have the index roots set in the ddl script
if ((full || !t.isCached())
&& !t.isTemp()
&& !t.isView()
&& (!t.isText() || !t.isDataReadOnly())) {
Index primary = t.getPrimaryIndex();
Node x = primary.first();
while (x != null) {
writeLine(w, t.getInsertStatement(x.getData()));
x = primary.next(x);
}
}
// fredt@users 20020221 - patch 513005 by sqlbob@users (RMP)
if (t.isDataReadOnly() && !t.isTemp() && !t.isText()) {
HsqlStringBuffer a = new HsqlStringBuffer("SET TABLE ");
a.append(t.getName().statementName);
a.append(" READONLY TRUE");
writeLine(w, a.toString());
}
}
w.close();
if (Trace.TRACE) {
Trace.trace(time - System.currentTimeMillis());
}
} catch (IOException e) {
throw Trace.error(Trace.FILE_IO_ERROR, file + " " + e);
}
}
/**
* Drops the specified user-defined view or table from this Database object.
*
* <p>The process of dropping a table or view includes:
*
* <OL>
* <LI>checking that the specified Session's currently connected User has the right to perform
* this operation and refusing to proceed if not by throwing.
* <LI>checking for referential constraints that conflict with this operation and refusing to
* proceed if they exist by throwing.
* <LI>removing the specified Table from this Database object.
* <LI>removing any exported foreign keys Constraint objects held by any tables referenced by
* the table to be dropped. This is especially important so that the dropped Table ceases to
* be referenced, eventually allowing its full garbage collection.
* <LI>
* </OL>
*
* <p>
*
* @param name of the table or view to drop
* @param ifExists if true and if the Table to drop does not exist, fail silently, else throw
* @param isView true if the name argument refers to a View
* @param session the connected context in which to perform this operation
* @throws SQLException if any of the checks listed above fail
*/
void dropTable(String name, boolean ifExists, boolean isView, Session session)
throws SQLException {
Table toDrop = null;
int dropIndex = -1;
int refererIndex = -1;
Enumeration constraints = null;
Constraint currentConstraint = null;
Table refTable = null;
boolean isRef = false;
boolean isSelfRef = false;
for (int i = 0; i < tTable.size(); i++) {
toDrop = (Table) tTable.get(i);
if (toDrop.equals(name, session) && isView == toDrop.isView()) {
dropIndex = i;
break;
} else {
toDrop = null;
}
}
if (dropIndex == -1) {
if (ifExists) {
return;
} else {
throw Trace.error(isView ? Trace.VIEW_NOT_FOUND : Trace.TABLE_NOT_FOUND, name);
}
}
constraints = toDrop.getConstraints().elements();
while (constraints.hasMoreElements()) {
currentConstraint = (Constraint) constraints.nextElement();
if (currentConstraint.getType() != Constraint.MAIN) {
continue;
}
refTable = currentConstraint.getRef();
isRef = (refTable != null);
isSelfRef = (isRef && toDrop.equals(refTable));
if (isRef && !isSelfRef) {
// cover the case where the referencing table
// may have already been dropped
for (int k = 0; k < tTable.size(); k++) {
if (refTable.equals(tTable.get(k))) {
refererIndex = k;
break;
}
}
if (refererIndex != -1) {
// tony_lai@users 20020820 - patch 595156
throw Trace.error(
Trace.INTEGRITY_CONSTRAINT_VIOLATION,
currentConstraint.getName().name + " table: " + refTable.getName().name);
}
}
}
tTable.remove(dropIndex);
removeExportedKeys(toDrop);
aAccess.removeDbObject(toDrop.getName());
triggerNameList.removeOwner(toDrop.tableName);
indexNameList.removeOwner(toDrop.tableName);
toDrop.drop();
session.setScripting(!toDrop.isTemp());
session.commit();
}
/**
* Determines if the authorizations are adequate to execute the compiled object. Completion
* requires the list of all database objects in a compiled statement.
*/
void checkAccessRights(Session session) {
if (targetTable != null && !targetTable.isTemp()) {
Grantee owner = targetTable.getOwner();
if (owner != null && owner.isSystem()) {
if (!session.getUser().isSystem()) {
throw Error.error(ErrorCode.X_42501, targetTable.getName().name);
}
}
if (!session.isProcessingScript) {
targetTable.checkDataReadOnly();
}
session.checkReadWrite();
}
if (session.isAdmin()) {
return;
}
for (int i = 0; i < sequences.length; i++) {
session.getGrantee().checkAccess(sequences[i]);
}
for (int i = 0; i < routines.length; i++) {
if (routines[i].isLibraryRoutine()) {
continue;
}
session.getGrantee().checkAccess(routines[i]);
}
for (int i = 0; i < rangeVariables.length; i++) {
RangeVariable range = rangeVariables[i];
if (range.rangeTable.getSchemaName() == SqlInvariants.SYSTEM_SCHEMA_HSQLNAME) {
continue;
}
session.getGrantee().checkSelect(range.rangeTable, range.usedColumns);
}
switch (type) {
case StatementTypes.CALL:
{
break;
}
case StatementTypes.INSERT:
{
session.getGrantee().checkInsert(targetTable, insertCheckColumns);
break;
}
case StatementTypes.SELECT_CURSOR:
break;
case StatementTypes.DELETE_WHERE:
{
session.getGrantee().checkDelete(targetTable);
break;
}
case StatementTypes.UPDATE_WHERE:
{
session.getGrantee().checkUpdate(targetTable, updateCheckColumns);
break;
}
case StatementTypes.MERGE:
{
session.getGrantee().checkInsert(targetTable, insertCheckColumns);
session.getGrantee().checkUpdate(targetTable, updateCheckColumns);
break;
}
}
}
