CREATE USER preslav IDENTIFIED BY "oracle" DEFAULT TABLESPACE USERS QUOTA 250M ON USERS TEMPORARY TABLESPACE TEMP;
GRANT CREATE SESSION, CREATE TABLE to preslav;
CREATE TABLE pktable ( pkno NUMBER(5) PRIMARY KEY, pkname VARCHAR2(50) NOT NULL, pkphone VARCHAR2(50));

CREATE PROCEDURE grant_schema(
    username VARCHAR2,
    grantee VARCHAR2)
AS
BEGIN
    FOR r IN (
        SELECT owner, table_name
        FROM all_tables
        WHERE owner = username
    )
    LOOP
        EXECUTE IMMEDIATE
            'GRANT SELECT, INSERT, ALTER, DELETE ON '||r.owner||'.'||r.table_name||' to ' || grantee;
    END LOOP;
END;

grant_schema('HR', 'preslav');
DROP USER preslav CASCADE;