Examples with Database com.wplatform.ddal.engine.Database used on opensource projects

Example 6 with Database

use of com.wplatform.ddal.engine.Database in project jdbc-shards by wplatform.

the class GrantRevoke method setGranteeName.

public void setGranteeName(String granteeName) {
    Database db = session.getDatabase();
    grantee = db.findUser(granteeName);
    if (grantee == null) {
        grantee = db.findRole(granteeName);
        if (grantee == null) {
            throw DbException.get(ErrorCode.USER_OR_ROLE_NOT_FOUND_1, granteeName);
        }
    }
}

Example 7 with Database

use of com.wplatform.ddal.engine.Database in project jdbc-shards by wplatform.

the class Explain method query.

@Override
public ResultInterface query(int maxrows) {
    Column column = new Column("PLAN", Value.STRING);
    Database db = session.getDatabase();
    ExpressionColumn expr = new ExpressionColumn(db, column);
    Expression[] expressions = { expr };
    result = new LocalResult(session, expressions, 1);
    if (maxrows >= 0) {
        String plan;
        if (executeCommand) {
            if (command.isQuery()) {
                command.query(maxrows);
            } else {
                command.update();
            }
            plan = command.getPlanSQL();
        } else {
            plan = command.getPlanSQL();
        }
        add(plan);
    }
    result.done();
    return result;
}

Example 8 with Database

use of com.wplatform.ddal.engine.Database in project jdbc-shards by wplatform.

the class Query method initOrder.

/**
     * Initialize the order by list. This call may extend the expressions list.
     *
     * @param session        the session
     * @param expressions    the select list expressions
     * @param expressionSQL  the select list SQL snippets
     * @param orderList      the order by list
     * @param visible        the number of visible columns in the select list
     * @param mustBeInResult all order by expressions must be in the select list
     * @param filters        the table filters
     */
static void initOrder(Session session, ArrayList<Expression> expressions, ArrayList<String> expressionSQL, ArrayList<SelectOrderBy> orderList, int visible, boolean mustBeInResult, ArrayList<TableFilter> filters) {
    Database db = session.getDatabase();
    for (SelectOrderBy o : orderList) {
        Expression e = o.expression;
        if (e == null) {
            continue;
        }
        // special case: SELECT 1 AS A FROM DUAL ORDER BY A
        // (oracle supports it, but only in order by, not in group by and
        // not in having):
        // SELECT 1 AS A FROM DUAL ORDER BY -A
        boolean isAlias = false;
        int idx = expressions.size();
        if (e instanceof ExpressionColumn) {
            // order by expression
            ExpressionColumn exprCol = (ExpressionColumn) e;
            String tableAlias = exprCol.getOriginalTableAliasName();
            String col = exprCol.getOriginalColumnName();
            for (int j = 0; j < visible; j++) {
                boolean found = false;
                Expression ec = expressions.get(j);
                if (ec instanceof ExpressionColumn) {
                    // select expression
                    ExpressionColumn c = (ExpressionColumn) ec;
                    found = db.equalsIdentifiers(col, c.getColumnName());
                    if (found && tableAlias != null) {
                        String ca = c.getOriginalTableAliasName();
                        if (ca == null) {
                            found = false;
                            if (filters != null) {
                                // select id from test order by test.id
                                for (int i = 0, size = filters.size(); i < size; i++) {
                                    TableFilter f = filters.get(i);
                                    if (db.equalsIdentifiers(f.getTableAlias(), tableAlias)) {
                                        found = true;
                                        break;
                                    }
                                }
                            }
                        } else {
                            found = db.equalsIdentifiers(ca, tableAlias);
                        }
                    }
                } else if (!(ec instanceof Alias)) {
                    continue;
                } else if (tableAlias == null && db.equalsIdentifiers(col, ec.getAlias())) {
                    found = true;
                } else {
                    Expression ec2 = ec.getNonAliasExpression();
                    if (ec2 instanceof ExpressionColumn) {
                        ExpressionColumn c2 = (ExpressionColumn) ec2;
                        String ta = exprCol.getSQL();
                        String tb = c2.getSQL();
                        String s2 = c2.getColumnName();
                        found = db.equalsIdentifiers(col, s2);
                        if (!db.equalsIdentifiers(ta, tb)) {
                            found = false;
                        }
                    }
                }
                if (found) {
                    idx = j;
                    isAlias = true;
                    break;
                }
            }
        } else {
            String s = e.getSQL();
            if (expressionSQL != null) {
                for (int j = 0, size = expressionSQL.size(); j < size; j++) {
                    String s2 = expressionSQL.get(j);
                    if (db.equalsIdentifiers(s2, s)) {
                        idx = j;
                        isAlias = true;
                        break;
                    }
                }
            }
        }
        if (!isAlias) {
            if (mustBeInResult) {
                throw DbException.get(ErrorCode.ORDER_BY_NOT_IN_RESULT, e.getSQL());
            }
            expressions.add(e);
            String sql = e.getSQL();
            expressionSQL.add(sql);
        }
        o.columnIndexExpr = ValueExpression.get(ValueInt.get(idx + 1));
        Expression expr = expressions.get(idx).getNonAliasExpression();
        o.expression = expr;
    }
}

Example 9 with Database

use of com.wplatform.ddal.engine.Database in project jdbc-shards by wplatform.

the class Comparison method getAdditional.

/**
     * Get an additional condition if possible. Example: given two conditions
     * A=B AND B=C, the new condition A=C is returned. Given the two conditions
     * A=1 OR A=2, the new condition A IN(1, 2) is returned.
     *
     * @param session the session
     * @param other   the second condition
     * @param and     true for AND, false for OR
     * @return null or the third condition
     */
Expression getAdditional(Session session, Comparison other, boolean and) {
    if (compareType == other.compareType && compareType == EQUAL) {
        boolean lc = left.isConstant();
        boolean rc = right.isConstant();
        boolean l2c = other.left.isConstant();
        boolean r2c = other.right.isConstant();
        String l = left.getSQL();
        String l2 = other.left.getSQL();
        String r = right.getSQL();
        String r2 = other.right.getSQL();
        if (and) {
            // must not compare constants. example: NOT(B=2 AND B=3)
            if (!(rc && r2c) && l.equals(l2)) {
                return new Comparison(session, EQUAL, right, other.right);
            } else if (!(rc && l2c) && l.equals(r2)) {
                return new Comparison(session, EQUAL, right, other.left);
            } else if (!(lc && r2c) && r.equals(l2)) {
                return new Comparison(session, EQUAL, left, other.right);
            } else if (!(lc && l2c) && r.equals(r2)) {
                return new Comparison(session, EQUAL, left, other.left);
            }
        } else {
            // a=b OR a=c
            Database db = session.getDatabase();
            if (rc && r2c && l.equals(l2)) {
                return new ConditionIn(db, left, New.arrayList(Arrays.asList(right, other.right)));
            } else if (rc && l2c && l.equals(r2)) {
                return new ConditionIn(db, left, New.arrayList(Arrays.asList(right, other.left)));
            } else if (lc && r2c && r.equals(l2)) {
                return new ConditionIn(db, right, New.arrayList(Arrays.asList(left, other.right)));
            } else if (lc && l2c && r.equals(r2)) {
                return new ConditionIn(db, right, New.arrayList(Arrays.asList(left, other.left)));
            }
        }
    }
    return null;
}

Example 10 with Database

use of com.wplatform.ddal.engine.Database in project jdbc-shards by wplatform.

the class Command method executeQuery.

/**
     * Execute a query and return the result.
     * This method prepares everything and calls {@link #query(int)} finally.
     *
     * @param maxrows    the maximum number of rows to return
     * @param scrollable if the result set must be scrollable (ignored)
     * @return the result set
     */
@Override
public ResultInterface executeQuery(int maxrows, boolean scrollable) {
    startTime = 0;
    Database database = session.getDatabase();
    Object sync = session;
    boolean callStop = true;
    synchronized (sync) {
        session.setCurrentCommand(this);
        try {
            while (true) {
                try {
                    return query(maxrows);
                } catch (DbException e) {
                    throw e;
                } catch (OutOfMemoryError e) {
                    callStop = false;
                    // there is a serious problem:
                    // the transaction may be applied partially
                    // in this case we need to panic:
                    // close the database
                    database.shutdownImmediately();
                    throw DbException.convert(e);
                } catch (Throwable e) {
                    throw DbException.convert(e);
                }
            }
        } catch (DbException e) {
            e = e.addSQL(sql);
            SQLException s = e.getSQLException();
            if (s.getErrorCode() == ErrorCode.OUT_OF_MEMORY) {
                callStop = false;
                database.shutdownImmediately();
                throw e;
            }
            throw e;
        } finally {
            if (callStop) {
                stop();
            }
        }
    }
}