/**
 * Overwrite this method to get the default schema name for the connection.
 * If you only need to change the statement that obtains the current schema then override
 *
 * @see AbstractJdbcDatabase#getConnectionSchemaNameCallStatement()
 */
protected String getConnectionSchemaName() {
    if (connection == null) {
        return null;
    }
    if (connection instanceof OfflineConnection) {
        return ((OfflineConnection) connection).getSchema();
    }

    try {
        SqlStatement currentSchemaStatement = getConnectionSchemaNameCallStatement();
        return ExecutorService.getInstance().getExecutor(this).
            queryForObject(currentSchemaStatement, String.class);
    } catch (Exception e) {
        LogService.getLog(getClass()).info(LogType.LOG, "Error getting default schema", e);
    }
    return null;
}
 

@Override
public void execute(final SqlStatement[] statements, final List<SqlVisitor> sqlVisitors) throws LiquibaseException {
    for (SqlStatement statement : statements) {
        if (statement.skipOnUnsupported() && !SqlGeneratorFactory.getInstance().supports(statement, this)) {
            continue;
        }
        LogService.getLog(getClass()).debug(LogType.LOG, "Executing Statement: " + statement);
        try {
            ExecutorService.getInstance().getExecutor(this).execute(statement, sqlVisitors);
        } catch (DatabaseException e) {
            if (statement.continueOnError()) {
                LogService.getLog(getClass()).severe(LogType.LOG, "Error executing statement '" + statement.toString() + "', but continuing", e);
            } else {
                throw e;
            }
        }
    }
}
 

@Test
public void testUpdateSQL() {
    enableLogging();

    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"" + alterText + "\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=address",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(DropForeignKeyConstraintStatement.class, statements[2].getClass());
}
 

@Test
public void testUpdateSQL() {
    enableLogging();

    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"ADD COLUMN new_column INT NULL\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=person",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(AddColumnStatement.class, statements[2].getClass());
}
 

@Test
public void testRollbackSQL() throws RollbackImpossibleException {
    enableLogging();

    SqlStatement[] statements = generateRollbackStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"DROP COLUMN new_column\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=person",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(DropColumnStatement.class, statements[2].getClass());
}
 

@Test
public void testUpdateSQL() {
    enableLogging();

    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"" + alterText + "\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=person",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(AddUniqueConstraintStatement.class, statements[2].getClass());
}
 

@Test
public void testRollbackSQL() throws RollbackImpossibleException {
    enableLogging();

    SqlStatement[] statements = generateRollbackStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"" + alterRollbackText + "\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=person",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(DropUniqueConstraintStatement.class, statements[2].getClass());
}
 

@Test
public void testUpdateSQL() {
    enableLogging();

    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"" + alterText + "\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=person",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(DropUniqueConstraintStatement.class, statements[2].getClass());
}
 

@Test
public void testUpdateSQL() {
    enableLogging();

    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"DROP COLUMN col_test\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=person",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(DropColumnStatement.class, statements[2].getClass());
}
 

@Test
public void testUpdateSQL() {
    enableLogging();

    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"ADD UNIQUE INDEX theIndexName (indexedColumn)\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=person",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(CreateIndexStatement.class, statements[2].getClass());
}
 

@Test
public void testUpdateSQL() {
    enableLogging();

    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"" + alterText + "\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=address",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(AddForeignKeyConstraintStatement.class, statements[2].getClass());
}
 

@Test
public void testRollbackSQL() throws RollbackImpossibleException {
    enableLogging();

    SqlStatement[] statements = generateRollbackStatements();
    Assertions.assertEquals(3, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"" + alterRollbackText + "\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=address",
            ((CommentStatement)statements[0]).getText());
    Assertions.assertEquals(CommentStatement.class, statements[1].getClass());
    Assertions.assertEquals(DropForeignKeyConstraintStatement.class, statements[2].getClass());
}
 

@Override
public SqlStatement[] generateStatements(final Database database) {
   final String[] columns = new String[this.columns.size()];
   int ii = 0;
   for (final ColumnConfig columnConfig : this.columns) {
      columns[ii++] = columnConfig.getName();
   }

   // Parse the string SRID into an integer.
   Integer srid = null;
   if (getSrid() != null) {
      srid = Integer.valueOf(getSrid());
   }

   final CreateSpatialIndexStatement statement = new CreateSpatialIndexStatement(
         getIndexName(), getCatalogName(), getSchemaName(), getTableName(), columns,
         getTablespace(), getGeometryType(), srid);
   return new SqlStatement[] { statement };
}
 

/**
 * Generates a {@link DropSpatialIndexStatement} followed by a {@link DropIndexStatement}, if
 * applicable. The first statement allows extra clean-up when dropping an index. The second
 * statement leverages the normal <code>DROP INDEX</code> logic.
 */
@Override
public SqlStatement[] generateStatements(final Database database) {
   final Collection<SqlStatement> statements = new ArrayList<SqlStatement>();
   // MySQL and PostgreSQL only need the normal DROP INDEX statement.
   if (!(database instanceof MySQLDatabase) && !(database instanceof PostgresDatabase)) {
      final DropSpatialIndexStatement dropSpatialIndex = new DropSpatialIndexStatement(
            this.indexName, this.catalogName, this.schemaName, this.tableName);
      statements.add(dropSpatialIndex);
   }

   // GeoDB doesn't use a tradition index structure so don't issue the normal DROP INDEX
   // statement.
   if (!(database instanceof DerbyDatabase) && !(database instanceof H2Database)) {
      final DropIndexStatement dropIndex = new DropIndexStatement(this.indexName,
            this.catalogName, this.schemaName, this.tableName, null);
      statements.add(dropIndex);
   }
   return statements.toArray(new SqlStatement[statements.size()]);
}
 

@Override
public SqlStatement[] generateStatements(Database database) {
    SqlStatement[] statements = super.generateStatements(database);
    if (!MSSQLDatabase.PRODUCT_NAME.equals(database.getDatabaseProductName())) {
    	return statements;
    }
    List<SqlStatement> wrappedStatements = new ArrayList<SqlStatement>(statements.length);
    for (SqlStatement statement : statements) {
        if (statement instanceof InsertStatement) {
            wrappedStatements.add(new InsertStatementMSSQL((InsertStatement) statement, identityInsertEnabled));
        } else {
            wrappedStatements.add(statement);
        }
    }
    return wrappedStatements.toArray(new SqlStatement[0]);
}
 

@Override
public SqlStatement[] generateStatements(Database database) {
  SqlStatement[] statements = super.generateStatements(database);
  if (!MSSQLDatabase.PRODUCT_NAME.equals(database.getDatabaseProductName())) {
  	return statements;
  }

  List<SqlStatement> extendedStatements = new ArrayList<SqlStatement>(statements.length);
  for (SqlStatement statement : statements) {
    if (statement instanceof CreateIndexStatement) {
      extendedStatements.add(new CreateIndexStatementMSSQL((CreateIndexStatement)statement, includedColumns, fillFactor));
    } else {
      extendedStatements.add(statement);
    }
  }

  return extendedStatements.toArray(new SqlStatement[0]);
}
 

@Override
   public SqlStatement[] generateStatements(Database database) {
SqlStatement[] statements = super.generateStatements(database);
   if (!MSSQLDatabase.PRODUCT_NAME.equals(database.getDatabaseProductName())) {
   	return statements;
   }
List<SqlStatement> wrappedStatements = new ArrayList<SqlStatement>(statements.length);
for (SqlStatement statement : statements) {
    if (statement instanceof InsertStatement) {
	wrappedStatements.add(new InsertStatementMSSQL((InsertStatement) statement, identityInsertEnabled));
    } else if(statement instanceof InsertSetStatement) {
        wrappedStatements.add(new InsertSetStatementMSSQL((InsertSetStatement) statement, identityInsertEnabled));
    } else {
	wrappedStatements.add(statement);
    }
}
return wrappedStatements.toArray(new SqlStatement[0]);
   }
 

@Override
public SqlStatement[] generateStatements(Database database) {
  SqlStatement[] statements = super.generateStatements(database);
  if (!MSSQLDatabase.PRODUCT_NAME.equals(database.getDatabaseProductName())) {
  	return statements;
  }
  List<SqlStatement> extendedStatements = new ArrayList<SqlStatement>(statements.length);

  for (SqlStatement statement : statements) {
    if (statement instanceof AddPrimaryKeyStatement) {
      extendedStatements.add(new AddPrimaryKeyStatementMSSQL((AddPrimaryKeyStatement)statement, fillFactor));
    } else {
      extendedStatements.add(statement);
    }
  }

  return extendedStatements.toArray(new SqlStatement[0]);
}
 

private Set<Integer> currentIdsInDatabaseChangeLogLockTable() throws DatabaseException {
    try {
        Executor executor = ExecutorService.getInstance().getExecutor(database);
        String idColumnName = database.escapeColumnName(database.getLiquibaseCatalogName(),
                database.getLiquibaseSchemaName(),
                database.getDatabaseChangeLogLockTableName(),
                "ID");
        String lockTableName = database.escapeTableName(database.getLiquibaseCatalogName(),
                database.getLiquibaseSchemaName(),
                database.getDatabaseChangeLogLockTableName());
        SqlStatement sqlStatement = new RawSqlStatement("SELECT " + idColumnName + " FROM " + lockTableName);
        List<Map<String, ?>> rows = executor.queryForList(sqlStatement);
        Set<Integer> ids = rows.stream().map(columnMap -> ((Number) columnMap.get("ID")).intValue()).collect(Collectors.toSet());
        database.commit();
        return ids;
    } catch (UnexpectedLiquibaseException ulie) {
        // It can happen with MariaDB Galera 10.1 that UnexpectedLiquibaseException is rethrown due the DB lock.
        // It is sufficient to just rollback transaction and retry in that case.
        if (ulie.getCause() != null && ulie.getCause() instanceof DatabaseException) {
            throw (DatabaseException) ulie.getCause();
        } else {
            throw ulie;
        }
    }
}
 

@Override
public void saveStatements(final Change change, final List<SqlVisitor> sqlVisitors, final Writer writer) throws
    IOException {
    SqlStatement[] statements = change.generateStatements(this);
    for (SqlStatement statement : statements) {
        for (Sql sql : SqlGeneratorFactory.getInstance().generateSql(statement, this)) {
            writer.append(sql.toSql()).append(sql.getEndDelimiter()).append(StreamUtil.getLineSeparator()).append(StreamUtil.getLineSeparator());
        }
    }
}
 

@Override
public void saveRollbackStatement(final Change change, final List<SqlVisitor> sqlVisitors, final Writer writer) throws IOException, LiquibaseException {
    SqlStatement[] statements = change.generateRollbackStatements(this);
    for (SqlStatement statement : statements) {
        for (Sql sql : SqlGeneratorFactory.getInstance().generateSql(statement, this)) {
            writer.append(sql.toSql()).append(sql.getEndDelimiter()).append("\n\n");
        }
    }
}
 

@Override
public Sql[] generateSql(MarkChangeSetRanStatement statement, Database database, SqlGeneratorChain sqlGeneratorChain) {
    ChangeSet changeSet = statement.getChangeSet();

    SqlStatement runStatement;
    try {
        if (statement.getExecType().equals(ChangeSet.ExecType.FAILED) || statement.getExecType().equals(ChangeSet.ExecType.SKIPPED)) {
            return new Sql[0]; //don't mark
        }

        String tag = null;
        for (Change change : changeSet.getChanges()) {
            if (change instanceof TagDatabaseChange) {
                TagDatabaseChange tagChange = (TagDatabaseChange) change;
                tag = tagChange.getTag();
            }
        }

        runStatement = new HiveInsertStatement(database.getLiquibaseCatalogName(), database.getLiquibaseSchemaName(), database.getDatabaseChangeLogTableName())
                .addColumnValue(changeSet.getId())
                .addColumnValue(changeSet.getAuthor())
                .addColumnValue(changeSet.getFilePath())
                .addColumnValue(DateTimeUtils.getCurrentTS("yyyy-MM-dd HH:mm:ss"))
                .addColumnValue(ChangeLogHistoryServiceFactory.getInstance().getChangeLogService(database).getNextSequenceValue())
                .addColumnValue(statement.getExecType().value)
                .addColumnValue(changeSet.generateCheckSum().toString())
                .addColumnValue(changeSet.getDescription())
                .addColumnValue(StringUtils.trimToEmpty(changeSet.getComments()))
                .addColumnValue(tag == null ? "NULL" : tag)
                .addColumnValue(ChangeLogHistoryServiceFactory.getInstance().getChangeLogService(database).getDeploymentId())
                .addColumnValue(changeSet.getContexts() == null || changeSet.getContexts().isEmpty() ? null : changeSet.getContexts().toString())
                .addColumnValue(changeSet.getLabels() == null || changeSet.getLabels().isEmpty() ? null : changeSet.getLabels().toString())
                .addColumnValue(LiquibaseUtil.getBuildVersion());
    } catch (LiquibaseException e) {
        throw new UnexpectedLiquibaseException(e);
    }

    return SqlGeneratorFactory.getInstance().generateSql(runStatement, database);
}
 

public static Sql[] generateSql(Database database, List<SqlStatement> statements) {
    List<Sql> sqls = new ArrayList<Sql>();
    SqlGeneratorFactory generatorFactory = SqlGeneratorFactory.getInstance();
    for (SqlStatement statement : statements) {
        sqls.addAll(Arrays.asList(generatorFactory.generateSql(statement, database)));
    }
    return sqls.toArray(new Sql[sqls.size()]);
}
 

public static Sql[] generateSql(Database database, SqlStatement... statements) {
    List<Sql> sqls = new ArrayList<Sql>();
    SqlGeneratorFactory generatorFactory = SqlGeneratorFactory.getInstance();
    for (SqlStatement statement : statements) {
        sqls.addAll(Arrays.asList(generatorFactory.generateSql(statement, database)));
    }
    return sqls.toArray(new Sql[sqls.size()]);
}
 

@Override
public void execute(SqlStatement[] statements, List<SqlVisitor> sqlVisitors) throws LiquibaseException {
    if (syncDdl) {
        List<SqlStatement> sqlStatementList = new ArrayList<SqlStatement>();
        sqlStatementList.add(UserSessionSettings.syncDdlStart());
        sqlStatementList.addAll(Arrays.asList(statements));
        sqlStatementList.add(UserSessionSettings.syncDdlStop());
        SqlStatement[] wrappedStatements = new SqlStatement[sqlStatementList.size()];
        sqlStatementList.toArray(wrappedStatements);
        super.execute(wrappedStatements, sqlVisitors);
    } else {
        super.execute(statements, sqlVisitors);
    }
}
 

@Override
public SqlStatement[] generateStatements( Database database )
{
    return PerconaChangeUtil.generateStatements(this,
                database,
                super.generateStatements(database));
}
 

@Override
public SqlStatement[] generateStatements( Database database )
{
    return PerconaChangeUtil.generateStatements(this,
                database,
                super.generateStatements(database));
}
 

@Override
public SqlStatement[] generateStatements( Database database )
{
    return PerconaChangeUtil.generateStatements(this,
                database,
                super.generateStatements(database));
}
 

@Test
public void testWithoutPercona() {
    PTOnlineSchemaChangeStatement.available = false;
    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(1, statements.length);
    Assertions.assertEquals(DropForeignKeyConstraintStatement.class, statements[0].getClass());
}
 

@Test
public void testUpdateSQLNoAlterSqlDryMode() {
    enableLogging();
    System.setProperty(Configuration.NO_ALTER_SQL_DRY_MODE, "true");

    SqlStatement[] statements = generateStatements();
    Assertions.assertEquals(1, statements.length);
    Assertions.assertEquals(CommentStatement.class, statements[0].getClass());
    Assertions.assertEquals("pt-online-schema-change "
            + "--alter-foreign-keys-method=auto "
            + "--nocheck-unique-key-change "
            + "--alter=\"" + alterText + "\" "
            + "--host=localhost --port=3306 --user=user --password=*** --execute D=testdb,t=address",
            ((CommentStatement)statements[0]).getText());
}