fix: EXPOSED-57 BatchInsertStatement can't be used with MySQL upsert (#…

…1754)

* fix: EXPOSED-57 BatchInsertStatement can't be used with MySQL upsert

Enable codeblock that was commented out by issue #129.
Add condition that prevents AssertionError if autoGeneratedKeys size mismatch
occurs with a dialect that supports a third affected-row value (namely MySQL,
MariaDB, and both related H2 modes).

Add KDocs explaining that returned value of InsertStatement.insertedCount is
calculated as the sum of individual statement values when used in a batch. Include
note that some vendors (MySQL-related dialects) return 2 if an existing row is
updated, so returned value from an upsert mimics the affected-row value from
the database.

Refactor test helper, excludingH2Version1, to use a pre-existing H2Dialect
function, isSecondVersion.

* Fix detekt issues causing max threshold build fail

* Revert "Fix detekt issues causing max threshold build fail"

This reverts commit 7c2c527.
Relevant Detekt issues are addressed in PR#1752

exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/statements/InsertStatement.kt

@@ -2,15 +2,23 @@ package org.jetbrains.exposed.sql.statements
 
 import org.jetbrains.exposed.sql.*
 import org.jetbrains.exposed.sql.statements.api.PreparedStatementApi
-import org.jetbrains.exposed.sql.vendors.PostgreSQLDialect
-import org.jetbrains.exposed.sql.vendors.currentDialect
+import org.jetbrains.exposed.sql.vendors.*
 import org.jetbrains.exposed.sql.vendors.inProperCase
 import java.sql.ResultSet
 import java.sql.SQLException
 import kotlin.properties.Delegates
 
 open class InsertStatement<Key : Any>(val table: Table, val isIgnore: Boolean = false) : UpdateBuilder<Int>(StatementType.INSERT, listOf(table)) {
 
+    /**
+     * Returns the number of rows affected by the insert operation.
+     *
+     * When returned by a `BatchInsertStatement` or `BatchUpsertStatement`, the returned value is calculated using the
+     * sum of the individual values generated by each statement.
+     *
+     * **Note**: Some vendors support returning the affected-row value of 2 if an existing row is updated by an upsert
+     * operation; please check the documentation.
+     */
     var insertedCount: Int by Delegates.notNull()
 
     var resultedValues: List<ResultRow>? = null
@@ -62,12 +70,10 @@ open class InsertStatement<Key : Any>(val table: Table, val isIgnore: Boolean =
                     }
                 }
 
-                /** TODO: https://github.com/JetBrains/Exposed/issues/129
-                 *  doesn't work with MySQL `INSERT ... ON DUPLICATE UPDATE`
-                 */
-//            assert(isIgnore || autoGeneratedKeys.isEmpty() || autoGeneratedKeys.size == inserted) {
-//                "Number of autoincs (${autoGeneratedKeys.size}) doesn't match number of batch entries ($inserted)"
-//            }
+                assert(isIgnore || autoGeneratedKeys.isEmpty() ||
+                           autoGeneratedKeys.size == inserted || currentDialect.supportsTernaryAffectedRowValues) {
+                    "Number of autoincs (${autoGeneratedKeys.size}) doesn't match number of batch entries ($inserted)"
+                }
             }
         }
 

exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/Default.kt

@@ -793,6 +793,9 @@ interface DatabaseDialect {
     val supportsSequenceAsGeneratedKeys: Boolean get() = supportsCreateSequence
     val supportsOnlyIdentifiersInGeneratedKeys: Boolean get() = false
 
+    /** Returns `true` if the dialect supports an upsert operation returning an affected-row value of 0, 1, or 2. */
+    val supportsTernaryAffectedRowValues: Boolean get() = false
+
     /** Returns`true` if the dialect supports schema creation. */
     val supportsCreateSchema: Boolean get() = true
 

exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/H2.kt

@@ -211,6 +211,9 @@ open class H2Dialect : VendorDialect(dialectName, H2DataTypeProvider, H2Function
     override val supportsSequenceAsGeneratedKeys: Boolean by lazy {
         resolveDelegatedDialect()?.supportsSequenceAsGeneratedKeys ?: super.supportsSequenceAsGeneratedKeys
     }
+    override val supportsTernaryAffectedRowValues: Boolean by lazy {
+        resolveDelegatedDialect()?.supportsTernaryAffectedRowValues ?: super.supportsTernaryAffectedRowValues
+    }
     override val supportsCreateSchema: Boolean by lazy { resolveDelegatedDialect()?.supportsCreateSchema ?: super.supportsCreateSchema }
     override val supportsSubqueryUnions: Boolean by lazy { resolveDelegatedDialect()?.supportsSubqueryUnions ?: super.supportsSubqueryUnions }
     override val supportsDualTableConcept: Boolean by lazy { resolveDelegatedDialect()?.supportsDualTableConcept ?: super.supportsDualTableConcept }

exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/vendors/Mysql.kt

@@ -205,6 +205,8 @@ open class MysqlDialect : VendorDialect(dialectName, MysqlDataTypeProvider, Mysq
 
     override val supportsCreateSequence: Boolean = false
 
+    override val supportsTernaryAffectedRowValues: Boolean = true
+
     override val supportsSubqueryUnions: Boolean = true
 
     override val supportsOrderByNullsFirstLast: Boolean = false

exposed-tests/src/main/kotlin/org/jetbrains/exposed/sql/tests/DatabaseTestsBase.kt

@@ -7,11 +7,11 @@ import org.jetbrains.exposed.sql.transactions.inTopLevelTransaction
 import org.jetbrains.exposed.sql.transactions.nullableTransactionScope
 import org.jetbrains.exposed.sql.transactions.transaction
 import org.jetbrains.exposed.sql.transactions.transactionManager
+import org.jetbrains.exposed.sql.vendors.H2Dialect
 import org.junit.Assume
 import org.junit.AssumptionViolatedException
 import org.testcontainers.containers.MySQLContainer
 import org.testcontainers.containers.PostgreSQLContainer
-import java.math.BigDecimal
 import java.sql.Connection
 import java.sql.SQLException
 import java.time.Duration
@@ -286,7 +286,7 @@ abstract class DatabaseTestsBase {
     }
 
     fun Transaction.excludingH2Version1(dbSettings: TestDB, statement: Transaction.(TestDB) -> Unit) {
-        if (dbSettings !in TestDB.allH2TestDB || db.isVersionCovers(BigDecimal("2.0"))) {
+        if (dbSettings !in TestDB.allH2TestDB || (db.dialect as H2Dialect).isSecondVersion) {
             statement(dbSettings)
         }
     }

exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/dml/UpsertTests.kt

@@ -7,11 +7,13 @@ import org.jetbrains.exposed.sql.SqlExpressionBuilder.concat
 import org.jetbrains.exposed.sql.SqlExpressionBuilder.less
 import org.jetbrains.exposed.sql.SqlExpressionBuilder.minus
 import org.jetbrains.exposed.sql.SqlExpressionBuilder.plus
+import org.jetbrains.exposed.sql.statements.BatchUpsertStatement
 import org.jetbrains.exposed.sql.tests.*
 import org.jetbrains.exposed.sql.tests.shared.assertEquals
 import org.jetbrains.exposed.sql.tests.shared.expectException
 import org.junit.Test
 import java.util.*
+import kotlin.properties.Delegates
 
 // Upsert implementation does not support H2 version 1
 // https://youtrack.jetbrains.com/issue/EXPOSED-30/Phase-Out-Support-for-H2-Version-1.x
@@ -21,31 +23,24 @@ class UpsertTests : DatabaseTestsBase() {
 
     @Test
     fun testUpsertWithPKConflict() {
-        val tester = object : Table("tester") {
-            val id = integer("id").autoIncrement()
-            val name = varchar("name", 64)
-
-            override val primaryKey = PrimaryKey(id)
-        }
-
-        withTables(tester) { testDb ->
+        withTables(AutoIncTable) { testDb ->
             excludingH2Version1(testDb) {
-                val id1 = tester.insert {
+                val id1 = AutoIncTable.insert {
                     it[name] = "A"
-                } get tester.id
+                } get AutoIncTable.id
 
-                tester.upsert {
+                AutoIncTable.upsert {
                     if (testDb in upsertViaMergeDB) it[id] = 2
                     it[name] = "B"
                 }
-                tester.upsert {
+                AutoIncTable.upsert {
                     it[id] = id1
                     it[name] = "C"
                 }
 
-                assertEquals(2, tester.selectAll().count())
-                val updatedResult = tester.select { tester.id eq id1 }.single()
-                assertEquals("C", updatedResult[tester.name])
+                assertEquals(2, AutoIncTable.selectAll().count())
+                val updatedResult = AutoIncTable.select { AutoIncTable.id eq id1 }.single()
+                assertEquals("C", updatedResult[AutoIncTable.name])
             }
         }
     }
@@ -424,6 +419,56 @@ class UpsertTests : DatabaseTestsBase() {
         }
     }
 
+    @Test
+    fun testInsertedCountWithBatchUpsert() {
+        withTables(AutoIncTable) { testDb ->
+            excludingH2Version1(testDb) {
+                // SQL Server requires statements to be executed before results can be obtained
+                val isNotSqlServer = testDb != TestDB.SQLSERVER
+                val data = listOf(1 to "A", 2 to "B", 3 to "C")
+                val newDataSize = data.size
+                var statement: BatchUpsertStatement by Delegates.notNull()
+
+                // all new rows inserted
+                AutoIncTable.batchUpsert(data, shouldReturnGeneratedValues = isNotSqlServer) { (id, name) ->
+                    statement = this
+                    this[AutoIncTable.id] = id
+                    this[AutoIncTable.name] = name
+                }
+                assertEquals(newDataSize, statement.insertedCount)
+
+                // all existing rows set to their current values
+                val isH2MysqlMode = testDb == TestDB.H2_MYSQL || testDb == TestDB.H2_MARIADB
+                var expected = if (isH2MysqlMode) 0 else newDataSize
+                AutoIncTable.batchUpsert(data, shouldReturnGeneratedValues = isNotSqlServer) { (id, name) ->
+                    statement = this
+                    this[AutoIncTable.id] = id
+                    this[AutoIncTable.name] = name
+                }
+                assertEquals(expected, statement.insertedCount)
+
+                // all existing rows updated & 1 new row inserted
+                val updatedData = data.map { it.first to "new${it.second}" } + (4 to "D")
+                expected = if (testDb in TestDB.mySqlRelatedDB) newDataSize * 2 + 1 else newDataSize + 1
+                AutoIncTable.batchUpsert(updatedData, shouldReturnGeneratedValues = isNotSqlServer) { (id, name) ->
+                    statement = this
+                    this[AutoIncTable.id] = id
+                    this[AutoIncTable.name] = name
+                }
+                assertEquals(expected, statement.insertedCount)
+
+                assertEquals(updatedData.size.toLong(), AutoIncTable.selectAll().count())
+            }
+        }
+    }
+
+    private object AutoIncTable : Table("auto_inc_table") {
+        val id = integer("id").autoIncrement()
+        val name = varchar("name", 64)
+
+        override val primaryKey = PrimaryKey(id)
+    }
+
     private object Words : Table("words") {
         val word = varchar("name", 64).uniqueIndex()
         val count = integer("count").default(1)