/**
* Initializes full text search functionality for this database. This adds the following Java
* functions to the database:
*
* <ul>
* <li>FTL_CREATE_INDEX(schemaNameString, tableNameString, columnListString)
* <li>FTL_SEARCH(queryString, limitInt, offsetInt): result set
* <li>FTL_REINDEX()
* <li>FTL_DROP_ALL()
* </ul>
*
* It also adds a schema FTL to the database where bookkeeping information is stored. This
* function may be called from a Java application, or by using the SQL statements:
*
* <pre>
* CREATE ALIAS IF NOT EXISTS FTL_INIT FOR
* "org.h2.fulltext.FullTextLucene2.init";
* CALL FTL_INIT();
* </pre>
*
* @param conn the connection
*/
public static void init(Connection conn) throws SQLException {
Statement stat = conn.createStatement();
stat.execute("CREATE SCHEMA IF NOT EXISTS " + SCHEMA);
stat.execute(
"CREATE TABLE IF NOT EXISTS "
+ SCHEMA
+ ".INDEXES(SCHEMA VARCHAR, TABLE VARCHAR, COLUMNS VARCHAR, PRIMARY KEY(SCHEMA, TABLE))");
stat.execute(
"CREATE ALIAS IF NOT EXISTS FTL_CREATE_INDEX FOR \""
+ FullTextLucene2.class.getName()
+ ".createIndex\"");
stat.execute(
"CREATE ALIAS IF NOT EXISTS FTL_SEARCH FOR \""
+ FullTextLucene2.class.getName()
+ ".search\"");
stat.execute(
"CREATE ALIAS IF NOT EXISTS FTL_SEARCH_DATA FOR \""
+ FullTextLucene2.class.getName()
+ ".searchData\"");
stat.execute(
"CREATE ALIAS IF NOT EXISTS FTL_REINDEX FOR \""
+ FullTextLucene2.class.getName()
+ ".reindex\"");
stat.execute(
"CREATE ALIAS IF NOT EXISTS FTL_DROP_ALL FOR \""
+ FullTextLucene2.class.getName()
+ ".dropAll\"");
try {
getIndexAccess(conn);
} catch (SQLException e) {
throw convertException(e);
}
}
/**
* Re-creates the full text index for this database. Calling this method is usually not needed, as
* the index is kept up-to-date automatically.
*
* @param conn the connection
*/
public static void reindex(Connection conn) throws SQLException {
init(conn);
removeAllTriggers(conn, TRIGGER_PREFIX);
removeIndexFiles(conn);
Statement stat = conn.createStatement();
ResultSet rs = stat.executeQuery("SELECT * FROM " + SCHEMA + ".INDEXES");
while (rs.next()) {
String schema = rs.getString("SCHEMA");
String table = rs.getString("TABLE");
createTrigger(conn, schema, table);
indexExistingRows(conn, schema, table);
}
}
/**
* Get the path of the Lucene index for this database.
*
* @param conn the database connection
* @return the path
*/
protected static String getIndexPath(Connection conn) throws SQLException {
Statement stat = conn.createStatement();
ResultSet rs = stat.executeQuery("CALL DATABASE_PATH()");
rs.next();
String path = rs.getString(1);
if (path == null) {
throw throwException("Fulltext search for in-memory databases is not supported.");
}
int index = path.lastIndexOf(':');
// position 1 means a windows drive letter is used, ignore that
if (index > 1) {
path = path.substring(index + 1);
}
rs.close();
return path;
}
/**
* Add the existing data to the index.
*
* @param conn the database connection
* @param schema the schema name
* @param table the table name
*/
protected static void indexExistingRows(Connection conn, String schema, String table)
throws SQLException {
FullTextLucene2.FullTextTrigger existing = new FullTextLucene2.FullTextTrigger();
existing.init(conn, schema, null, table, false, Trigger.INSERT);
String sql =
"SELECT * FROM "
+ StringUtils.quoteIdentifier(schema)
+ "."
+ StringUtils.quoteIdentifier(table);
ResultSet rs = conn.createStatement().executeQuery(sql);
int columnCount = rs.getMetaData().getColumnCount();
while (rs.next()) {
Object[] row = new Object[columnCount];
for (int i = 0; i < columnCount; i++) {
row[i] = rs.getObject(i + 1);
}
// existing.fire(conn, null, row);
existing.insert(row, false);
}
existing.commitIndex();
}
/**
* Create the trigger.
*
* @param conn the database connection
* @param schema the schema name
* @param table the table name
*/
protected static void createTrigger(Connection conn, String schema, String table)
throws SQLException {
Statement stat = conn.createStatement();
String trigger =
StringUtils.quoteIdentifier(schema)
+ "."
+ StringUtils.quoteIdentifier(TRIGGER_PREFIX + table);
stat.execute("DROP TRIGGER IF EXISTS " + trigger);
StringBuilder buff = new StringBuilder("CREATE TRIGGER IF NOT EXISTS ");
// the trigger is also called on rollback because transaction rollback
// will not undo the changes in the Lucene index
buff.append(trigger)
.append(" AFTER INSERT, UPDATE, DELETE, ROLLBACK ON ")
.append(StringUtils.quoteIdentifier(schema))
.append('.')
.append(StringUtils.quoteIdentifier(table))
.append(" FOR EACH ROW CALL \"")
.append(FullTextLucene2.FullTextTrigger.class.getName())
.append('\"');
stat.execute(buff.toString());
}
/**
* Drops all full text indexes from the database.
*
* @param conn the connection
*/
public static void dropAll(Connection conn) throws SQLException {
Statement stat = conn.createStatement();
stat.execute("DROP SCHEMA IF EXISTS " + SCHEMA);
removeAllTriggers(conn, TRIGGER_PREFIX);
removeIndexFiles(conn);
}