Examples with ExecCursorTableReference org.apache.derby.iapi.sql.execute.ExecCursorTableReference used on opensource projects

Example 1 with ExecCursorTableReference

use of org.apache.derby.iapi.sql.execute.ExecCursorTableReference in project derby by apache.

the class EmbedResultSet method updateRow.

/**
 * JDBC 2.0
 *
 * Update the underlying database with the new contents of the
 * current row.  Cannot be called when on the insert row.
 *
 * @exception SQLException if a database-access error occurs, or
 * if called when on the insert row
 */
public void updateRow() throws SQLException {
    synchronized (getConnectionSynchronization()) {
        checksBeforeUpdateOrDelete("updateRow", -1);
        // Check that the cursor is not positioned on insertRow
        checkNotOnInsertRow();
        setupContextStack();
        LanguageConnectionContext lcc = getLanguageConnectionContext(getEmbedConnection());
        StatementContext statementContext = null;
        try {
            if (// nothing got updated on this row
            currentRowHasBeenUpdated == false)
                // nothing to do since no updates were made to this row
                return;
            // now construct the update where current of sql
            boolean foundOneColumnAlready = false;
            StringBuffer updateWhereCurrentOfSQL = new StringBuffer("UPDATE ");
            CursorActivation activation = lcc.lookupCursorActivation(getCursorName());
            ExecCursorTableReference targetTable = activation.getPreparedStatement().getTargetTable();
            // got the underlying (schema.)table name
            updateWhereCurrentOfSQL.append(getFullBaseTableName(targetTable));
            updateWhereCurrentOfSQL.append(" SET ");
            ResultDescription rd = theResults.getResultDescription();
            for (int i = 1; i <= rd.getColumnCount(); i++) {
                // in this for loop we are constructing columnname=?,... part of the update sql
                if (columnGotUpdated[i - 1]) {
                    // if the column got updated, do following
                    if (foundOneColumnAlready)
                        updateWhereCurrentOfSQL.append(",");
                    // using quotes around the column name to preserve case sensitivity
                    updateWhereCurrentOfSQL.append(IdUtil.normalToDelimited(rd.getColumnDescriptor(i).getName()) + "=?");
                    foundOneColumnAlready = true;
                }
            }
            // using quotes around the cursor name to preserve case sensitivity
            updateWhereCurrentOfSQL.append(" WHERE CURRENT OF " + IdUtil.normalToDelimited(getCursorName()));
            StatementContext currSC = lcc.getStatementContext();
            Activation parentAct = null;
            if (currSC != null) {
                parentAct = currSC.getActivation();
            }
            // Context used for preparing, don't set any timeout (use 0)
            statementContext = lcc.pushStatementContext(isAtomic, false, updateWhereCurrentOfSQL.toString(), null, false, 0L);
            // A priori, the new statement context inherits the activation of
            // the existing statementContext, so that that activation ends up
            // as parent of the new activation 'act' created below, which will
            // be the activation of the pushed statement context.
            statementContext.setActivation(parentAct);
            org.apache.derby.iapi.sql.PreparedStatement ps = lcc.prepareInternalStatement(updateWhereCurrentOfSQL.toString());
            Activation act = ps.getActivation(lcc, false);
            statementContext.setActivation(act);
            // in this for loop we are assigning values for parameters in sql constructed earlier with columnname=?,...
            for (int i = 1, paramPosition = 0; i <= rd.getColumnCount(); i++) {
                if (// if the column got updated, do following
                columnGotUpdated[i - 1])
                    act.getParameterValueSet().getParameterForSet(paramPosition++).setValue(updateRow.getColumn(i));
            }
            // Don't set any timeout when updating rows (use 0)
            // Execute the update where current of sql.
            org.apache.derby.iapi.sql.ResultSet rs = ps.executeSubStatement(activation, act, true, 0L);
            SQLWarning w = act.getWarnings();
            if (w != null) {
                addWarning(w);
            }
            act.close();
            // For forward only resultsets, after a update, the ResultSet will be positioned right before the next row.
            if (getType() == TYPE_FORWARD_ONLY) {
                currentRow = null;
            } else {
                movePosition(RELATIVE, 0, "relative");
            }
            lcc.popStatementContext(statementContext, null);
            InterruptStatus.restoreIntrFlagIfSeen(lcc);
        } catch (Throwable t) {
            throw closeOnTransactionError(t);
        } finally {
            if (statementContext != null)
                lcc.popStatementContext(statementContext, null);
            restoreContextStack();
            initializeUpdateRowModifiers();
        }
    }
}

Example 2 with ExecCursorTableReference

use of org.apache.derby.iapi.sql.execute.ExecCursorTableReference in project derby by apache.

the class EmbedResultSet method insertRow.

/**
 * JDBC 2.0
 *
 * Insert the contents of the insert row into the result set and the
 * database. Must be on the insert row when this method is called.
 *
 * @exception SQLException
 *                if a database-access error occurs, if called when not on
 *                the insert row, or if all non-nullable columns in the
 *                insert row have not been given a value
 */
public void insertRow() throws SQLException {
    synchronized (getConnectionSynchronization()) {
        checksBeforeInsert();
        setupContextStack();
        LanguageConnectionContext lcc = getLanguageConnectionContext(getEmbedConnection());
        StatementContext statementContext = null;
        try {
            /*
                 * construct the insert statement
                 *
                 * If no values have been supplied for a column, it will be set 
                 * to the column's default value, if any. 
                 * If no default value had been defined, the default value of a 
                 * nullable column is set to NULL.
                 */
            boolean foundOneColumnAlready = false;
            StringBuffer insertSQL = new StringBuffer("INSERT INTO ");
            StringBuffer valuesSQL = new StringBuffer("VALUES (");
            CursorActivation activation = lcc.lookupCursorActivation(getCursorName());
            ExecCursorTableReference targetTable = activation.getPreparedStatement().getTargetTable();
            // got the underlying (schema.)table name
            insertSQL.append(getFullBaseTableName(targetTable));
            ResultDescription rd = theResults.getResultDescription();
            insertSQL.append(" (");
            // and values (?) ,... part of the insert sql
            for (int i = 1; i <= rd.getColumnCount(); i++) {
                if (foundOneColumnAlready) {
                    insertSQL.append(",");
                    valuesSQL.append(",");
                }
                // using quotes around the column name
                // to preserve case sensitivity
                insertSQL.append(IdUtil.normalToDelimited(rd.getColumnDescriptor(i).getName()));
                if (columnGotUpdated[i - 1]) {
                    valuesSQL.append("?");
                } else {
                    valuesSQL.append("DEFAULT");
                }
                foundOneColumnAlready = true;
            }
            insertSQL.append(") ");
            valuesSQL.append(") ");
            insertSQL.append(valuesSQL);
            StatementContext currSC = lcc.getStatementContext();
            Activation parentAct = null;
            if (currSC != null) {
                parentAct = currSC.getActivation();
            }
            // Context used for preparing, don't set any timeout (use 0)
            statementContext = lcc.pushStatementContext(isAtomic, false, insertSQL.toString(), null, false, 0L);
            // A priori, the new statement context inherits the activation
            // of the existing statementContext, so that that activation
            // ends up as parent of the new activation 'act' created below,
            // which will be the activation of the pushed statement
            // context.
            statementContext.setActivation(parentAct);
            org.apache.derby.iapi.sql.PreparedStatement ps = lcc.prepareInternalStatement(insertSQL.toString());
            Activation act = ps.getActivation(lcc, false);
            statementContext.setActivation(act);
            // in sql constructed earlier VALUES (?, ..)
            for (int i = 1, paramPosition = 0; i <= rd.getColumnCount(); i++) {
                // if the column got updated, do following
                if (columnGotUpdated[i - 1]) {
                    act.getParameterValueSet().getParameterForSet(paramPosition++).setValue(updateRow.getColumn(i));
                }
            }
            // Don't see any timeout when inserting rows (use 0)
            // execute the insert
            org.apache.derby.iapi.sql.ResultSet rs = ps.executeSubStatement(activation, act, true, 0L);
            act.close();
            lcc.popStatementContext(statementContext, null);
            InterruptStatus.restoreIntrFlagIfSeen(lcc);
        } catch (Throwable t) {
            throw closeOnTransactionError(t);
        } finally {
            if (statementContext != null)
                lcc.popStatementContext(statementContext, null);
            restoreContextStack();
        }
    }
}

Example 3 with ExecCursorTableReference

use of org.apache.derby.iapi.sql.execute.ExecCursorTableReference in project derby by apache.

the class CurrentOfNode method bindNonVTITables.

// 
// FromTable interface
// 
/**
 * Binding this FromTable means finding the prepared statement
 * for the cursor and creating the result columns (the columns
 * updatable on that cursor).
 *
 * We expect someone else to verify that the target table
 * of the positioned update or delete is the table under this cursor.
 *
 * @param dataDictionary	The DataDictionary to use for binding
 * @param fromListParam		FromList to use/append to.
 *
 * @return	ResultSetNode		Returns this.
 *
 * @exception StandardException		Thrown on error
 */
@Override
ResultSetNode bindNonVTITables(DataDictionary dataDictionary, FromList fromListParam) throws StandardException {
    // verify that the cursor exists
    preStmt = getCursorStatement();
    if (preStmt == null) {
        throw StandardException.newException(SQLState.LANG_CURSOR_NOT_FOUND, cursorName);
    }
    preStmt.rePrepare(getLanguageConnectionContext());
    // for checking that the right columns are updatable)
    if (preStmt.getUpdateMode() != CursorNode.UPDATE) {
        String printableString = (cursorName == null) ? "" : cursorName;
        throw StandardException.newException(SQLState.LANG_CURSOR_NOT_UPDATABLE, printableString);
    }
    ExecCursorTableReference refTab = preStmt.getTargetTable();
    String schemaName = refTab.getSchemaName();
    exposedTableName = makeTableName(null, refTab.getExposedName());
    baseTableName = makeTableName(schemaName, refTab.getBaseName());
    SchemaDescriptor tableSchema = getSchemaDescriptor(refTab.getSchemaName());
    /*
		** This will only happen when we are binding against a publication
		** dictionary w/o the schema we are interested in.
		*/
    if (tableSchema == null) {
        throw StandardException.newException(SQLState.LANG_SCHEMA_DOES_NOT_EXIST, refTab.getSchemaName());
    }
    /* Create dependency on target table, in case table not named in 
		 * positioned update/delete.  Make sure we find the table descriptor,
		 * we may fail to find it if we are binding a publication.
		 */
    TableDescriptor td = getTableDescriptor(refTab.getBaseName(), tableSchema);
    if (td == null) {
        throw StandardException.newException(SQLState.LANG_TABLE_NOT_FOUND, refTab.getBaseName());
    }
    /*
		** Add all the result columns from the target table.
		** For now, all updatable cursors have all columns
		** from the target table.  In the future, we should
		** relax this so that the cursor may do a partial
		** read and then the current of should make sure that
		** it can go to the base table to get all of the 
		** columns needed by the referencing positioned
		** DML.  In the future, we'll probably need to get
		** the result columns from preparedStatement and
		** turn them into an RCL that we can run with.
		*/
    setResultColumns(new ResultColumnList(getContextManager()));
    ColumnDescriptorList cdl = td.getColumnDescriptorList();
    int cdlSize = cdl.size();
    for (int index = 0; index < cdlSize; index++) {
        /* Build a ResultColumn/BaseColumnNode pair for the column */
        ColumnDescriptor colDesc = cdl.elementAt(index);
        BaseColumnNode bcn = new BaseColumnNode(colDesc.getColumnName(), exposedTableName, colDesc.getType(), getContextManager());
        ResultColumn rc = new ResultColumn(colDesc, bcn, getContextManager());
        /* Build the ResultColumnList to return */
        getResultColumns().addResultColumn(rc);
    }
    /* Assign the tableNumber */
    if (// allow re-bind, in which case use old number
    tableNumber == -1)
        tableNumber = getCompilerContext().getNextTableNumber();
    return this;
}