Question

I have three entities, in which i try to save only 1 entity right now. All the three entities are shown below :-

1. Student Entity

     <class name="com.school.Student" table="TABLE_STUDENT">
        <id name="id" type="long">
            <column name="ST_ID" />
            <generator class="native" />
        </id>
        <property name="name" type="string" column="ST_NAME"/>
        <many-to-one name="studentSection" class="com.school.Section" fetch="select">
            <column name="SECTION_ID" not-null="true" />
        </many-to-one> 
        <many-to-one name="studentSportsTeam" class="com.school.SportsTeam" fetch="select">
            <column name="SPORTS_TEAM" not-null="true" />
        </many-to-one>
     </class>

2. Section Entity

     <class name="com.school.Section" table="TABLE_SECTION">
         <id name="sectionId" type="string">
            <column name="SECTION_ID" />
            <generator class="assigned" />
        </id>
        <property name="floor" type="string" column="SEC_FLOOR"/>
        <property name="capcacity" type="int" column="SEC_CAPACITY"/>
        <set name="studentDetails" inverse="true" lazy="true" table="TABLE_STUDENT" fetch="select">
            <key>
                <column name="SECTION_ID" not-null="true" />
            </key>
            <one-to-many class="com.school.Student" />
        </set>
     </class>

3. SprotsTeam Entity :-

    <class name="com.school.SportsTeam" table="TABLE_SPORTS">
         <id name="sportsTeamId" type="string">
            <column name="SPORTS_TEAM" />
            <generator class="assigned" />
        </id>
        <property name="noOfPlayers" type="int" column="SPORTS_PLAYER_NUM"/>
        <property name="captainName" type="string" column="SPORTS_CAPTAIN_NAME"/>
        <set name="playerDetails" inverse="true" lazy="true" table="TABLE_STUDENT" fetch="select">
            <key>
                <column name="SPORTS_TEAM" not-null="true" />
            </key>
            <one-to-many class="com.school.Student" />
        </set>
     </class>

Now if i try to save Student Entity with proper Section and SportsTeam details, it takes a lot of time to persist it into the database. Currently i am running it for around 10000 students and this process (only persisting) takes around 15 mins. I added some loggers to calculate the complete time.

Now i need to reduce this time, as we will shorty move from 10,000 to 1 million records, and as calculated it takes very long time.. I need to reduce the time , how can i do that??

As Required, also the schema is as below :-

TABLE STUDENT :

ST_ID               NUMBER,
ST_NAME             VARCHAR(40),
SECTION_ID          VARCHAR(10),
SPORTS_TEAM         VARCHAR(10)

TABLE_SECTION :

SECTION_ID          VARCHAR(10),
SEC_FLOOR           VARCHAR(2),
SEC_CAPACITY        NUMBER

TABLE_SPORTS :

SPORTS_TEAM                  VARCHAR(10),
SPORTS_PLAYER_NUM            NUMBER,
SPORTS_CAPTAIN_NAME          VARCHAR(40)

Please help

Answer 1

Consider batch inserts.

Moreover, if this batch inserts is just for once i.e. as a part of migration process, then IMO, you can consider dropping all primary keys — and any other indices, on the tables, and then insert the records. After that re-create all those. Hopefully, you would notice a significant improvement.