Generic translation does not rely entirely on types

src/qir/ast/QIRDBNode.java

@@ -36,7 +36,7 @@ public final class QIRDBNode<DBRepr> extends QIRNode {
      */
     public QIRDBNode(final DBDriver<DBRepr> driver, final QIRNode toTranslate) throws NoSuchElementException {
         super(toTranslate.sourceSection);
-        setType(toTranslate.getType().get(), toTranslate.getTypeDriver());
+        toTranslate.getType().ifPresent(t -> setType(t, toTranslate.getTypeDriver()));
         this.driver = driver;
         this.translation = driver.translate(toTranslate);
     }
@@ -45,6 +45,10 @@ public final class QIRDBNode<DBRepr> extends QIRNode {
         return translation;
     }
 
+    public final DBDriver<DBRepr> getDriver() {
+        return driver;
+    }
+
     @Override
     public final String toString() {
         return "DBNode(" + translation + ")";

src/qir/driver/QIRGenericTranslation.java

@@ -65,7 +65,14 @@ final class QIRGenericTranslation implements IQIRVisitor<QIRNode> {
     public final QIRNode visit(final QIRProject qirProject) {
         if (!(qirProject.getTypeDriver() instanceof MEMDriver))
             return new QIRDBNode<>(qirProject.getTypeDriver(), qirProject);
-        return new QIRProject(qirProject.getSourceSection(), qirProject.getFormatter().accept(this), qirProject.getChild().accept(this));
+        final QIRNode child = qirProject.getChild().accept(this);
+
+        if (child instanceof QIRDBNode)
+            try {
+                return new QIRDBNode<>(((QIRDBNode<?>) child).getDriver(), new QIRProject(qirProject.getSourceSection(), qirProject.getFormatter(), child));
+            } catch (QIRException e) {
+            }
+        return new QIRProject(qirProject.getSourceSection(), qirProject.getFormatter().accept(this), child);
     }
 
     @Override
@@ -77,6 +84,13 @@ final class QIRGenericTranslation implements IQIRVisitor<QIRNode> {
     public final QIRNode visit(final QIRFilter qirFilter) {
         if (!(qirFilter.getTypeDriver() instanceof MEMDriver))
             return new QIRDBNode<>(qirFilter.getTypeDriver(), qirFilter);
+        final QIRNode child = qirFilter.getChild().accept(this);
+
+        if (child instanceof QIRDBNode)
+            try {
+                return new QIRDBNode<>(((QIRDBNode<?>) child).getDriver(), new QIRFilter(qirFilter.getSourceSection(), qirFilter.getFilter(), child));
+            } catch (QIRException e) {
+            }
         return new QIRFilter(qirFilter.getSourceSection(), qirFilter.getFilter().accept(this), qirFilter.getChild().accept(this));
     }
 
@@ -84,6 +98,13 @@ final class QIRGenericTranslation implements IQIRVisitor<QIRNode> {
     public final QIRNode visit(final QIRGroupBy qirGroupBy) {
         if (!(qirGroupBy.getTypeDriver() instanceof MEMDriver))
             return new QIRDBNode<>(qirGroupBy.getTypeDriver(), qirGroupBy);
+        final QIRNode child = qirGroupBy.getChild().accept(this);
+
+        if (child instanceof QIRDBNode)
+            try {
+                return new QIRDBNode<>(((QIRDBNode<?>) child).getDriver(), new QIRGroupBy(qirGroupBy.getSourceSection(), qirGroupBy.getGroup(), child));
+            } catch (QIRException e) {
+            }
         return new QIRGroupBy(qirGroupBy.getSourceSection(), qirGroupBy.getGroup().accept(this), qirGroupBy.getChild().accept(this));
     }
 
@@ -91,6 +112,13 @@ final class QIRGenericTranslation implements IQIRVisitor<QIRNode> {
     public final QIRNode visit(final QIRSortBy qirSortBy) {
         if (!(qirSortBy.getTypeDriver() instanceof MEMDriver))
             return new QIRDBNode<>(qirSortBy.getTypeDriver(), qirSortBy);
+        final QIRNode child = qirSortBy.getChild().accept(this);
+
+        if (child instanceof QIRDBNode)
+            try {
+                return new QIRDBNode<>(((QIRDBNode<?>) child).getDriver(), new QIRSortBy(qirSortBy.getSourceSection(), qirSortBy.getSort(), qirSortBy.getIsAscending(), child));
+            } catch (QIRException e) {
+            }
         return new QIRSortBy(qirSortBy.getSourceSection(), qirSortBy.getSort().accept(this), qirSortBy.getIsAscending().accept(this), qirSortBy.getChild().accept(this));
     }
 
@@ -124,7 +152,7 @@ final class QIRGenericTranslation implements IQIRVisitor<QIRNode> {
 
     @Override
     public final <DBRepr> QIRNode visit(final QIRDBNode<DBRepr> qirDBNode) {
-        throw new QIRException("Should not visit QIRDBNode in generic translation.");
+        return qirDBNode;
     }
 
     @Override

src/qir/driver/hbase/HBaseDriver.java

@@ -85,7 +85,7 @@ public final class HBaseDriver extends DBDriver<HBaseQuery> {
 
     @Override
     public HBaseQuery translate(final QIRNode query) {
-        return query.accept(new HBaseQueryTranslator(conf));
+        return query.accept(new HBaseQueryTranslator(conf, dbName, configFile));
     }
 
     @Override

src/qir/driver/hbase/HBaseQueryTranslator.java

@@ -24,9 +24,13 @@ import qir.util.QIRException;
  */
 final class HBaseQueryTranslator extends QIRTranslator<HBaseQuery> {
     private final Configuration conf;
+    private final String dbName;
+    private final String dbConfig;
 
-    HBaseQueryTranslator(final Configuration conf) {
+    HBaseQueryTranslator(final Configuration conf, final String dbName, final String dbConfig) {
         this.conf = conf;
+        this.dbName = dbName;
+        this.dbConfig = dbConfig;
     }
 
     @Override
@@ -43,6 +47,9 @@ final class HBaseQueryTranslator extends QIRTranslator<HBaseQuery> {
     @Override
     public final HBaseQuery visit(QIRScan qirScan) {
         if (qirScan.getTable() instanceof QIRTable && ((QIRTable) qirScan.getTable()).getDbName() instanceof QIRString && ((QIRTable) qirScan.getTable()).getConfigFile() instanceof QIRString) {
+            final QIRTable table = (QIRTable) qirScan.getTable();
+            if (!((QIRString) table.getDbName()).getValue().equals(dbName) || !((QIRString) table.getConfigFile()).getValue().equals(dbConfig))
+                throw new QIRException("Subquery for another database detected.");
             return new HBaseQuery(new Scan(), (String) ((QIRBaseValue<?>) ((QIRTable) qirScan.getTable()).getSchemaName()).getValue() + ":" +
                             (String) ((QIRBaseValue<?>) ((QIRTable) qirScan.getTable()).getTableName()).getValue());
         }

src/qir/driver/sql/HiveDriver.java

@@ -17,7 +17,7 @@ public final class HiveDriver extends SQLStringDriver {
 
     @Override
     public String translate(final QIRNode query) {
-        return query.accept(new HiveStringTranslator());
+        return query.accept(new HiveStringTranslator(dbName, configFile));
     }
 
     @Override

src/qir/driver/sql/HiveStringTranslator.java

@@ -19,6 +19,10 @@ import qir.ast.operator.QIROperator;
 import qir.util.QIRException;
 
 public class HiveStringTranslator extends SQLStringTranslator {
+    public HiveStringTranslator(String dbName, String dbConfig) {
+        super(dbName, dbConfig);
+    }
+
     @Override
     public final String visit(final QIRApply qirApply) {
         // TODO: Improve implementation

src/qir/driver/sql/OracleDriver.java

@@ -12,7 +12,7 @@ import qir.util.QIRException;
  */
 public final class OracleDriver extends SQLStringDriver {
     public static final String dbName = "Oracle";
-    private static final SQLStringTranslator translator = new SQLStringTranslator();
+    private final SQLStringTranslator translator = new SQLStringTranslator(dbName, configFile);
 
     public OracleDriver(final String configFile) {
         super(configFile);

src/qir/driver/sql/PostgreSQLDriver.java

@@ -18,7 +18,7 @@ public final class PostgreSQLDriver extends SQLStringDriver {
 
     @Override
     public String translate(final QIRNode query) {
-        return query.accept(new SQLStringTranslator());
+        return query.accept(new SQLStringTranslator(dbName, configFile));
     }
 
     @Override

src/qir/driver/sql/SQLStringTranslator.java

@@ -35,6 +35,21 @@ public class SQLStringTranslator extends QIRTranslator<String> {
      */
     private Map<String, String> prolog = new HashMap<>();
 
+    /**
+     * The name of the database the query will be sent to.
+     */
+    private final String dbName;
+
+    /**
+     * The configuration file of the database the query will be sent to.
+     */
+    private final String dbConfig;
+
+    public SQLStringTranslator(final String dbName, final String dbConfig) {
+        this.dbName = dbName;
+        this.dbConfig = dbConfig;
+    }
+
     public final Map<String, String> popProlog() {
         final Map<String, String> res = prolog;
         prolog = new HashMap<>();
@@ -51,8 +66,12 @@ public class SQLStringTranslator extends QIRTranslator<String> {
 
     @Override
     public final String visit(final QIRScan qirScan) {
-        if (qirScan.getTable() instanceof QIRTable && ((QIRTable) qirScan.getTable()).getDbName() instanceof QIRString && ((QIRTable) qirScan.getTable()).getConfigFile() instanceof QIRString)
+        if (qirScan.getTable() instanceof QIRTable && ((QIRTable) qirScan.getTable()).getDbName() instanceof QIRString && ((QIRTable) qirScan.getTable()).getConfigFile() instanceof QIRString) {
+            final QIRTable table = (QIRTable) qirScan.getTable();
+            if (!((QIRString) table.getDbName()).getValue().equals(dbName) || !((QIRString) table.getConfigFile()).getValue().equals(dbConfig))
+                throw new QIRException("Subquery for another database detected.");
             return "select * from " + qirScan.getTable().accept(this);
+        }
         throw new QIRException("QIR SQL Scan not implemented for table type: " + qirScan.getTable().getClass());
     }
 

src/qir/types/QIRFunctionType.java

@@ -39,6 +39,7 @@ public final class QIRFunctionType extends QIRType {
     }
 
     @Override
+    /* TODO: Fix contravariance */
     protected final boolean isSubtypeOfAux(final QIRType other) {
         return other instanceof QIRFunctionType && argumentType.isSubtypeOf(((QIRFunctionType) other).argumentType) && returnType.isSubtypeOf(((QIRFunctionType) other).returnType);
     }

src/qir/typing/QIRSpecificTypeSystem.java

@@ -153,7 +153,8 @@ public abstract class QIRSpecificTypeSystem extends QIRTypeSystem {
     /**
      * Throws a {@link QIRTypeErrorException} if the actual {@link QIRType} and the expected
      * {@link QIRType} do not share a common subtype in the sense of
-     * {@link QIRType#isSubtypeOf(QIRType)}.
+     * {@link QIRType#isSubtypeOf(QIRType)}. TODO: Fix implementation or change name to
+     * checkEitherSubtype.
      *
      * @param actual The actual {@link QIRType} of the expression.
      * @param expected The expected {@link QIRType} for the expression.