When calling the saveAll method of my JpaRepository with a long List from the service layer, trace logging of Hibernate shows single SQL statements being issued per entity.

Can I force it to do a bulk insert (i.e. multi-row) without needing to manually fiddle with EntityManger, transactions etc. or even raw SQL statement strings?

With multi-row insert I mean not just transitioning from:

start transaction

INSERT INTO table VALUES (1, 2)

end transaction

start transaction

INSERT INTO table VALUES (3, 4)

end transaction

start transaction

INSERT INTO table VALUES (5, 6)

end transaction

start transaction

INSERT INTO table VALUES (1, 2)

INSERT INTO table VALUES (3, 4)

INSERT INTO table VALUES (5, 6)

end transaction

but instead to:

start transaction

INSERT INTO table VALUES (1, 2), (3, 4), (5, 6)

end transaction

In PROD I'm using CockroachDB, and the difference in performance is significant.

Below is a minimal example that reproduces the problem (H2 for simplicity).

./src/main/kotlin/ThingService.kt:

package things

import org.springframework.boot.autoconfigure.SpringBootApplication

import org.springframework.boot.runApplication

import org.springframework.web.bind.annotation.RestController

import org.springframework.web.bind.annotation.GetMapping

import org.springframework.data.jpa.repository.JpaRepository

import javax.persistence.Entity

import javax.persistence.Id

import javax.persistence.GeneratedValue

interface ThingRepository : JpaRepository {

@RestController

class ThingController(private val repository: ThingRepository) {

@GetMapping("/test_trigger")

fun trigger() {

val things: MutableList = mutableListOf()

for (i in 3000..3013) {

things.add(Thing(i))

repository.saveAll(things)

@Entity

data class Thing (

var value: Int,

@GeneratedValue

var id: Long = -1

@SpringBootApplication

class Application {

fun main(args: Array) {

runApplication(*args)

./src/main/resources/application.properties:

jdbc.driverClassName = org.h2.Driver

jdbc.url = jdbc:h2:mem:db

jdbc.username = sa

jdbc.password = sa

hibernate.dialect=org.hibernate.dialect.H2Dialect

hibernate.hbm2ddl.auto=create

spring.jpa.generate-ddl = true

spring.jpa.show-sql = true

spring.jpa.properties.hibernate.jdbc.batch_size = 10

spring.jpa.properties.hibernate.order_inserts = true

spring.jpa.properties.hibernate.order_updates = true

spring.jpa.properties.hibernate.jdbc.batch_versioned_data = true

./build.gradle.kts:

import org.jetbrains.kotlin.gradle.tasks.KotlinCompile

plugins {

val kotlinVersion = "1.2.30"

id("org.springframework.boot") version "2.0.2.RELEASE"

id("org.jetbrains.kotlin.jvm") version kotlinVersion

id("org.jetbrains.kotlin.plugin.spring") version kotlinVersion

id("org.jetbrains.kotlin.plugin.jpa") version kotlinVersion

id("io.spring.dependency-management") version "1.0.5.RELEASE"

version = "1.0.0-SNAPSHOT"

tasks.withType {

kotlinOptions {

jvmTarget = "1.8"

freeCompilerArgs = listOf("-Xjsr305=strict")

repositories {

mavenCentral()

dependencies {

compile("org.springframework.boot:spring-boot-starter-web")

compile("org.springframework.boot:spring-boot-starter-data-jpa")

compile("org.jetbrains.kotlin:kotlin-stdlib-jdk8")

compile("org.jetbrains.kotlin:kotlin-reflect")

compile("org.hibernate:hibernate-core")

compile("com.h2database:h2")

./gradlew bootRun

Trigger DB INSERTs:

curl http://localhost:8080/test_trigger

Log output:

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: select thing0_.id as id1_0_0_, thing0_.value as value2_0_0_ from thing thing0_ where thing0_.id=?

Hibernate: call next value for hibernate_sequence

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

Hibernate: insert into thing (value, id) values (?, ?)

To get a bulk insert with Sring Boot and Spring Data JPA you need only two things:

set the option spring.jpa.properties.hibernate.jdbc.batch_size to appropriate value you need (for example: 20).

use saveAll() method of your repo with the list of entities prepared for inserting.

Working example is here.

Regarding the transformation of the insert statement into something like this:

INSERT INTO table VALUES (1, 2), (3, 4), (5, 6)

the such is available in PostgreSQL: you can set the option reWriteBatchedInserts to true in jdbc connection string:

jdbc:postgresql://localhost:5432/db?reWriteBatchedInserts=true

then jdbc driver will do this transformation.

Additional info about batching you can find here.

UPDATED

UPDATED

When calling the saveAll method of my JpaRepository with a long List from the service layer, trace logging of Hibernate shows single SQL statements being issued per entity.Can I force it to do a bulk ...