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−/*
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− * This Source Code Form is subject to the terms of the Mozilla Public
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− * License, v. 2.0.  If a copy of the MPL was not distributed with this
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− * file, You can obtain one at http://mozilla.org/MPL/2.0/.
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− *
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− * Copyright 2008-2015 MonetDB B.V.
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− */
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−
+
−package nl.cwi.monetdb.embedded;
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−
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−import nl.cwi.monetdb.embedded.column.Column;
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−
+
−import java.io.*;
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−import java.sql.SQLException;
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−
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−/**
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− * A single connection to a MonetDB database instance
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− * Communication between Java and native C is done via JNI.
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− * <br/>
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− * <strong>Note</strong>: You can have only one nl.cwi.monetdb.embedded MonetDB database running per JVM process.
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− */
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−public class MonetDBEmbeddedConnection {
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−
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−	private final long connectionPointer;
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−
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−	public MonetDBEmbeddedConnection(long connectionPointer) {
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−		this.connectionPointer = connectionPointer;
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−	}
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−
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−	protected long getConnectionPointer() {
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−		return connectionPointer;
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−	}
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−
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−	/**
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−	 * Execute an SQL query in an nl.cwi.monetdb.embedded database.
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−	 * 
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−	 * @param query The SQL query string
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−	 * @return The query result object, {@code null} if the database is not running
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−	 * @throws SQLException
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−	 */
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−	public EmbeddedQueryResult createQuery(String query) throws SQLException {
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−		String queryString = query;
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−		if (!queryString.endsWith(";")) {
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−			queryString += ";";
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−		}
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−		return queryWrapper(queryString, true, this.connectionPointer);
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−	}
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−
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−    /**
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−     * Begins a transaction in nl.cwi.monetdb.embedded database.
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−     *
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−     * @throws SQLException
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−     */
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−	public void startTransaction() throws SQLException {
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−		this.createQuery("START TRANSACTION;").close();
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−	}
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−
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−    /**
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−     * Commits a transaction in nl.cwi.monetdb.embedded database.
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−     *
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−     * @throws SQLException
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−     */
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−	public void commit() throws SQLException {
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−		this.createQuery("COMMIT;").close();
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−	}
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−
+
−    /**
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−     * Rollbacks a transaction in nl.cwi.monetdb.embedded database.
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−     *
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−     * @throws SQLException
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−     */
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−	public void rollback() throws SQLException {
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−		this.createQuery("ROLLBACK;").close();
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−	}
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−
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−    /**
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−     * Performs a Lists the the existing tables with schemas on the system
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−     *
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−     * @param listSystemTables List system's tables as well (default true)
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−     * @return The query result object, {@code null} if the database is not running
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−     * @throws SQLException
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−     */
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−    public EmbeddedQueryResult listTables(boolean listSystemTables) throws SQLException {
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−        String query = "select schemas.name as sn, tables.name as tn from sys.tables join sys.schemas on tables.schema_id=schemas.id";
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−        if (!listSystemTables) {
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−            query += " where tables.system=false order by sn, tn";
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−        }
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−        return this.createQuery(query + ";");
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−    }
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−
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−    /**
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−     * Performs a SELECT * FROM a table  in nl.cwi.monetdb.embedded database.
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−     *
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−     * @param tableName The name of the table
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−     * @return The query result object, {@code null} if the database is not running
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−     * @throws SQLException
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−     */
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−	public EmbeddedQueryResult readTable(String tableName) throws SQLException {
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−        return this.createQuery("SELECT * FROM " + tableName + ";");
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−    }
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−
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−    /**
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−     * Check if a table exists  in nl.cwi.monetdb.embedded database.
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−     *
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−     * @param tableName The name of the table
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−     * @return If a the table exists or not
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−     * @throws SQLException
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−     */
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−    public boolean checkTableExists(String tableName) throws SQLException {
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−        EmbeddedQueryResult eqr = this.listTables(true);
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−        Column<String> tablenames = (Column<String>) eqr.getColumn(0);
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−        boolean res = false;
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−        for (String str: tablenames.getAllValues()) {
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−            if(str.equals(tableName)) {
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−                res = true;
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−            }
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−        }
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−        eqr.close();
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−        return res;
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−    }
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−
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−    /**
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−     * Lists the table fields and types in nl.cwi.monetdb.embedded database.
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−     *
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−     * @param tableName The name of the table
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−     * @return
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−     * @throws SQLException
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−     */
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−    public String[] listFields(String tableName) throws SQLException {
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−        if(!this.checkTableExists(tableName)) {
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−            throw  new SQLException("The table " + tableName + " doesn't exist!!");
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−        }
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−        EmbeddedQueryResult eqr = this.createQuery("select columns.name as name from sys.columns join sys.tables on columns.table_id=tables.id where tables.name='" + tableName + "';");
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−        String[] res = (String[]) eqr.getColumn(0).getAllValues();
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−        eqr.close();
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−        return res;
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−    }
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−
+
−	/**
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−	 * Execute an SQL query in an nl.cwi.monetdb.embedded database.
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−	 * 
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−	 * @param query The SQL query string
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−	 * @return The query result object, {@code null} if the database is not running
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−	 * @throws SQLException
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−	 */
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−	private native EmbeddedQueryResult queryWrapper(String query, boolean execute, long connectionPointer) throws SQLException;
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−
+
−}