COciSchema

public function alterColumn($table, $column, $type)
{
    $type=$this->getColumnType($type);
    $sql='ALTER TABLE ' . $this->quoteTableName($table) . ' MODIFY '
        . $this->quoteColumnName($column) . ' '
        . $this->getColumnType($type);
    return $sql;
}

public function checkIntegrity($check=true,$schema='')
{
    if($schema==='')
        $schema=$this->getDefaultSchema();
    $mode=$check ? 'ENABLE' : 'DISABLE';
    foreach($this->getTableNames($schema) as $table)
    {
        $constraints=$this->getDbConnection()
            ->createCommand("SELECT CONSTRAINT_NAME FROM USER_CONSTRAINTS WHERE TABLE_NAME=:t AND OWNER=:o")
            ->queryColumn(array(':t'=>$table,':o'=>$schema));
        foreach($constraints as $constraint)
            $this->getDbConnection()
                ->createCommand("ALTER TABLE \"{$schema}\".\"{$table}\" {$mode} CONSTRAINT \"{$constraint}\"")
                ->execute();
    }
}

protected function createColumn($column)
{
    $c=new COciColumnSchema;
    $c->name=$column['COLUMN_NAME'];
    $c->rawName=$this->quoteColumnName($c->name);
    $c->allowNull=$column['NULLABLE']==='Y';
    $c->isPrimaryKey=strpos($column['KEY'],'P')!==false;
    $c->isForeignKey=false;
    $c->init($column['DATA_TYPE'],$column['DATA_DEFAULT']);
    $c->comment=$column['COLUMN_COMMENT']===null ? '' : $column['COLUMN_COMMENT'];

    return $c;
}

protected function createCommandBuilder()
{
    return new COciCommandBuilder($this);
}

public function dropIndex($name, $table)
{
    return 'DROP INDEX '.$this->quoteTableName($name);
}

protected function findColumns($table)
{
    $schemaName=$table->schemaName;
    $tableName=$table->name;

    $sql=<<<EOD
SELECT a.column_name, a.data_type ||
case
    when data_precision is not null
        then '(' || a.data_precision ||
                case when a.data_scale > 0 then ',' || a.data_scale else '' end
            || ')'
    when data_type = 'DATE' then ''
    when data_type = 'NUMBER' then ''
    else '(' || to_char(a.data_length) || ')'
end as data_type,
a.nullable, a.data_default,
(   SELECT D.constraint_type
    FROM ALL_CONS_COLUMNS C
    inner join ALL_constraints D on D.OWNER = C.OWNER and D.constraint_name = C.constraint_name
    WHERE C.OWNER = B.OWNER
       and C.table_name = B.object_name
       and C.column_name = A.column_name
       and D.constraint_type = 'P') as Key,
com.comments as column_comment
FROM ALL_TAB_COLUMNS A
inner join ALL_OBJECTS B ON b.owner = a.owner and ltrim(B.OBJECT_NAME) = ltrim(A.TABLE_NAME)
LEFT JOIN all_col_comments com ON (A.owner = com.owner AND A.table_name = com.table_name AND A.column_name = com.column_name)
WHERE
a.owner = '{$schemaName}'
and (b.object_type = 'TABLE' or b.object_type = 'VIEW')
and b.object_name = '{$tableName}'
ORDER by a.column_id
EOD;

    $command=$this->getDbConnection()->createCommand($sql);

    if(($columns=$command->queryAll())===array()){
        return false;
    }

    foreach($columns as $column)
    {
        $c=$this->createColumn($column);

        $table->columns[$c->name]=$c;
        if($c->isPrimaryKey)
        {
            if($table->primaryKey===null)
                $table->primaryKey=$c->name;
            elseif(is_string($table->primaryKey))
                $table->primaryKey=array($table->primaryKey,$c->name);
            else
                $table->primaryKey[]=$c->name;
            $table->sequenceName='';
            $c->autoIncrement=true;
        }
    }
    return true;
}

protected function findConstraints($table)
{
    $sql=<<<EOD
    SELECT D.constraint_type as CONSTRAINT_TYPE, C.COLUMN_NAME, C.position, D.r_constraint_name,
            E.table_name as table_ref, f.column_name as column_ref,
            C.table_name
    FROM ALL_CONS_COLUMNS C
    inner join ALL_constraints D on D.OWNER = C.OWNER and D.constraint_name = C.constraint_name
    left join ALL_constraints E on E.OWNER = D.r_OWNER and E.constraint_name = D.r_constraint_name
    left join ALL_cons_columns F on F.OWNER = E.OWNER and F.constraint_name = E.constraint_name and F.position = c.position
    WHERE C.OWNER = '{$table->schemaName}'
       and C.table_name = '{$table->name}'
       and D.constraint_type <> 'P'
    order by d.constraint_name, c.position
EOD;
    $command=$this->getDbConnection()->createCommand($sql);
    foreach($command->queryAll() as $row)
    {
        if($row['CONSTRAINT_TYPE']==='R')   // foreign key
        {
            $name = $row["COLUMN_NAME"];
            $table->foreignKeys[$name]=array($row["TABLE_REF"], $row["COLUMN_REF"]);
            if(isset($table->columns[$name]))
                $table->columns[$name]->isForeignKey=true;
        }

    }
}

protected function findTableNames($schema='')
{
    if($schema==='')
    {
        $sql=<<<EOD
SELECT table_name, '{$schema}' as table_schema FROM user_tables
EOD;
        $command=$this->getDbConnection()->createCommand($sql);
    }
    else
    {
        $sql=<<<EOD
SELECT object_name as table_name, owner as table_schema FROM all_objects
WHERE object_type = 'TABLE' AND owner=:schema
EOD;
        $command=$this->getDbConnection()->createCommand($sql);
        $command->bindParam(':schema',$schema);
    }

    $rows=$command->queryAll();
    $names=array();
    foreach($rows as $row)
    {
        if($schema===$this->getDefaultSchema() || $schema==='')
            $names[]=$row['TABLE_NAME'];
        else
            $names[]=$row['TABLE_SCHEMA'].'.'.$row['TABLE_NAME'];
    }
    return $names;
}

public function getDefaultSchema()
{
    if (!strlen($this->_defaultSchema))
    {
        $this->setDefaultSchema(strtoupper($this->getDbConnection()->username));
    }

    return $this->_defaultSchema;
}

protected function getSchemaTableName($table)
{
    $table = strtoupper($table);
    if(count($parts= explode('.', str_replace('"','',$table))) > 1)
        return array($parts[0], $parts[1]);
    else
        return array($this->getDefaultSchema(),$parts[0]);
}

protected function loadTable($name)
{
    $table=new COciTableSchema;
    $this->resolveTableNames($table,$name);

    if(!$this->findColumns($table))
        return null;
    $this->findConstraints($table);

    return $table;
}

public function quoteSimpleColumnName($name)
{
    return '"'.$name.'"';
}

public function quoteSimpleTableName($name)
{
    return '"'.$name.'"';
}

public function renameTable($table, $newName)
{
    return 'ALTER TABLE ' . $this->quoteTableName($table) . ' RENAME TO ' . $this->quoteTableName($newName);
}

public function resetSequence($table,$value=null)
{
    if($table->sequenceName===null)
        return;

    if($value!==null)
        $value=(int)$value;
    else
    {
        $value=(int)$this->getDbConnection()
            ->createCommand("SELECT MAX(\"{$table->primaryKey}\") FROM {$table->rawName}")
            ->queryScalar();
        $value++;
    }
    $this->getDbConnection()
        ->createCommand("DROP SEQUENCE \"{$table->name}_SEQ\"")
        ->execute();
    $this->getDbConnection()
        ->createCommand("CREATE SEQUENCE \"{$table->name}_SEQ\" START WITH {$value} INCREMENT BY 1 NOMAXVALUE NOCACHE")
        ->execute();
}

protected function resolveTableNames($table,$name)
{
    $parts=explode('.',str_replace('"','',$name));
    if(isset($parts[1]))
    {
        $schemaName=$parts[0];
        $tableName=$parts[1];
    }
    else
    {
        $schemaName=$this->getDefaultSchema();
        $tableName=$parts[0];
    }

    $table->name=$tableName;
    $table->schemaName=$schemaName;
    if($schemaName===$this->getDefaultSchema())
        $table->rawName=$this->quoteTableName($tableName);
    else
        $table->rawName=$this->quoteTableName($schemaName).'.'.$this->quoteTableName($tableName);
}

public function setDefaultSchema($schema)
{
    $this->_defaultSchema=$schema;
}