HHH-15179 - Move support for MySQL versions older than 5.7 into community dialects

Signed-off-by: Jan Schatteman <jschatte@redhat.com>

hibernate-community-dialects/src/main/java/org/hibernate/community/dialect/MySQLLegacySqlAstTranslator.java

@@ -0,0 +1,167 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.community.dialect;
+
+import org.hibernate.engine.spi.SessionFactoryImplementor;
+import org.hibernate.query.sqm.ComparisonOperator;
+import org.hibernate.sql.ast.spi.AbstractSqlAstTranslator;
+import org.hibernate.sql.ast.tree.Statement;
+import org.hibernate.sql.ast.tree.cte.CteStatement;
+import org.hibernate.sql.ast.tree.expression.Expression;
+import org.hibernate.sql.ast.tree.expression.Literal;
+import org.hibernate.sql.ast.tree.expression.Summarization;
+import org.hibernate.sql.ast.tree.from.QueryPartTableReference;
+import org.hibernate.sql.ast.tree.from.ValuesTableReference;
+import org.hibernate.sql.ast.tree.predicate.BooleanExpressionPredicate;
+import org.hibernate.sql.ast.tree.select.QueryGroup;
+import org.hibernate.sql.ast.tree.select.QueryPart;
+import org.hibernate.sql.ast.tree.select.QuerySpec;
+import org.hibernate.sql.exec.spi.JdbcOperation;
+
+/**
+ * A SQL AST translator for MySQL.
+ *
+ * @author Christian Beikov
+ */
+public class MySQLLegacySqlAstTranslator<T extends JdbcOperation> extends AbstractSqlAstTranslator<T> {
+
+	public MySQLLegacySqlAstTranslator(SessionFactoryImplementor sessionFactory, Statement statement) {
+		super( sessionFactory, statement );
+	}
+
+	@Override
+	protected void renderExpressionAsClauseItem(Expression expression) {
+		expression.accept( this );
+	}
+
+	@Override
+	public void visitBooleanExpressionPredicate(BooleanExpressionPredicate booleanExpressionPredicate) {
+		final boolean isNegated = booleanExpressionPredicate.isNegated();
+		if ( isNegated ) {
+			appendSql( "not(" );
+		}
+		booleanExpressionPredicate.getExpression().accept( this );
+		if ( isNegated ) {
+			appendSql( CLOSE_PARENTHESIS );
+		}
+	}
+
+	@Override
+	protected String getForShare(int timeoutMillis) {
+		return getDialect().getVersion().isSameOrAfter( 8 ) ? " for share" : " lock in share mode";
+	}
+
+	protected boolean shouldEmulateFetchClause(QueryPart queryPart) {
+		// Check if current query part is already row numbering to avoid infinite recursion
+		return useOffsetFetchClause( queryPart ) && getQueryPartForRowNumbering() != queryPart
+				&& getDialect().supportsWindowFunctions() && !isRowsOnlyFetchClauseType( queryPart );
+	}
+
+	@Override
+	public void visitQueryGroup(QueryGroup queryGroup) {
+		if ( shouldEmulateFetchClause( queryGroup ) ) {
+			emulateFetchOffsetWithWindowFunctions( queryGroup, true );
+		}
+		else {
+			super.visitQueryGroup( queryGroup );
+		}
+	}
+
+	@Override
+	public void visitQuerySpec(QuerySpec querySpec) {
+		if ( shouldEmulateFetchClause( querySpec ) ) {
+			emulateFetchOffsetWithWindowFunctions( querySpec, true );
+		}
+		else {
+			super.visitQuerySpec( querySpec );
+		}
+	}
+
+	@Override
+	public void visitValuesTableReference(ValuesTableReference tableReference) {
+		emulateValuesTableReferenceColumnAliasing( tableReference );
+	}
+
+	@Override
+	public void visitQueryPartTableReference(QueryPartTableReference tableReference) {
+		if ( getDialect().getVersion().isSameOrAfter( 8 ) ) {
+			super.visitQueryPartTableReference( tableReference );
+		}
+		else {
+			emulateQueryPartTableReferenceColumnAliasing( tableReference );
+		}
+	}
+
+	@Override
+	public void visitOffsetFetchClause(QueryPart queryPart) {
+		if ( !isRowNumberingCurrentQueryPart() ) {
+			renderCombinedLimitClause( queryPart );
+		}
+	}
+
+	@Override
+	protected void renderSearchClause(CteStatement cte) {
+		// MySQL does not support this, but it's just a hint anyway
+	}
+
+	@Override
+	protected void renderCycleClause(CteStatement cte) {
+		// MySQL does not support this, but it can be emulated
+	}
+
+	@Override
+	protected void renderComparison(Expression lhs, ComparisonOperator operator, Expression rhs) {
+		renderComparisonDistinctOperator( lhs, operator, rhs );
+	}
+
+	@Override
+	protected void renderPartitionItem(Expression expression) {
+		if ( expression instanceof Literal ) {
+			appendSql( "'0'" );
+		}
+		else if ( expression instanceof Summarization ) {
+			Summarization summarization = (Summarization) expression;
+			renderCommaSeparated( summarization.getGroupings() );
+			appendSql( " with " );
+			appendSql( summarization.getKind().sqlText() );
+		}
+		else {
+			expression.accept( this );
+		}
+	}
+
+	@Override
+	public boolean supportsRowValueConstructorSyntaxInSet() {
+		return false;
+	}
+
+	@Override
+	public boolean supportsRowValueConstructorSyntaxInInList() {
+		return getDialect().getVersion().isSameOrAfter( 5, 7 );
+	}
+
+	@Override
+	protected boolean supportsRowValueConstructorSyntaxInQuantifiedPredicates() {
+		return false;
+	}
+
+	@Override
+	protected boolean supportsIntersect() {
+		return false;
+	}
+
+	@Override
+	protected boolean supportsDistinctFromPredicate() {
+		// It supports a proprietary operator
+		return true;
+	}
+
+	@Override
+	protected String getFromDual() {
+		return " from dual";
+	}
+}

hibernate-core/src/main/java/org/hibernate/dialect/MySQLDialect.java

@@ -80,12 +80,14 @@ import static org.hibernate.exception.spi.TemplatedViolatedConstraintNameExtract
 import static org.hibernate.type.SqlTypes.*;
 
 /**
- * A {@linkplain Dialect SQL dialect} for MySQL 5 and above.
+ * A {@linkplain Dialect SQL dialect} for MySQL 5.7 and above.
  *
  * @author Gavin King
  */
 public class MySQLDialect extends Dialect {
 
+	private static final DatabaseVersion MINIMUM_VERSION = DatabaseVersion.make( 5, 7 );
+
 	private final UniqueDelegate uniqueDelegate = new MySQLUniqueDelegate( this );
 	private final MySQLStorageEngine storageEngine = createStorageEngine();
 	private final SizeStrategy sizeStrategy = new SizeStrategyImpl() {
@@ -111,7 +113,7 @@ public class MySQLDialect extends Dialect {
 	private final int maxVarbinaryLength;
 
 	public MySQLDialect() {
-		this( DatabaseVersion.make( 5, 0 ) );
+		this( MINIMUM_VERSION );
 	}
 
 	public MySQLDialect(DatabaseVersion version) {
@@ -128,6 +130,11 @@ public class MySQLDialect extends Dialect {
 		maxVarbinaryLength = maxVarbinaryLength( getMySQLVersion() );
 	}
 
+	@Override
+	protected DatabaseVersion getMinimumSupportedVersion() {
+		return MINIMUM_VERSION;
+	}
+
 	@Override
 	protected void initDefaultProperties() {
 		super.initDefaultProperties();
@@ -161,11 +168,9 @@ public class MySQLDialect extends Dialect {
 				return "bit";
 
 			case TIMESTAMP:
-				return getMySQLVersion().isBefore( 5, 7 )
+				return "datetime($p)";
-								? "datetime" : "datetime($p)";
 			case TIMESTAMP_WITH_TIMEZONE:
-				return getMySQLVersion().isBefore( 5, 7 )
+				return "timestamp($p)";
-								? "timestamp" : "timestamp($p)";
 			case NUMERIC:
 				// it's just a synonym
 				return columnType( DECIMAL );
@@ -221,11 +226,9 @@ public class MySQLDialect extends Dialect {
 		super.registerColumnTypes( typeContributions, serviceRegistry );
 		final DdlTypeRegistry ddlTypeRegistry = typeContributions.getTypeConfiguration().getDdlTypeRegistry();
 
-		if ( getMySQLVersion().isSameOrAfter( 5, 7 ) ) {
 		// MySQL 5.7 brings JSON native support with a dedicated datatype
 		// https://dev.mysql.com/doc/refman/5.7/en/json.html
 		ddlTypeRegistry.addDescriptor( new DdlTypeImpl( JSON, "json", this ) );
-		}
 
 		ddlTypeRegistry.addDescriptor( new DdlTypeImpl( GEOMETRY, "geometry", this ) );
 
@@ -346,15 +349,10 @@ public class MySQLDialect extends Dialect {
 	}
 
 	private static int maxVarbinaryLength(DatabaseVersion version) {
-		return version.isBefore( 5 ) ? 255 : 65_535;
+		return 65_535;
 	}
 
 	private static int maxVarcharLength(DatabaseVersion version, int bytesPerCharacter) {
-		// max length for VARCHAR changed in 5.0.3
-		if ( version.isBefore( 5 ) ) {
-			return 255;
-		}
-		else {
 		switch ( bytesPerCharacter ) {
 			case 1:
 				return 65_535;
@@ -367,7 +365,6 @@ public class MySQLDialect extends Dialect {
 				return 16_383;
 		}
 	}
-	}
 
 	@Override
 	public int getMaxVarcharLength() {
@@ -501,10 +498,6 @@ public class MySQLDialect extends Dialect {
 				.setUseParenthesesWhenNoArgs( false )
 				.register();
 
-		if ( getMySQLVersion().isBefore( 5, 7 ) ) {
-			functionFactory.sysdateParens();
-		}
-		else {
 		// MySQL timestamp type defaults to precision 0 (seconds) but
 		// we want the standard default precision of 6 (microseconds)
 		functionFactory.sysdateExplicitMicros();
@@ -514,7 +507,6 @@ public class MySQLDialect extends Dialect {
 				functionFactory.hypotheticalOrderedSetAggregates_windowEmulation();
 			}
 		}
-		}
 
 		functionFactory.listagg_groupConcat();
 	}
@@ -526,9 +518,7 @@ public class MySQLDialect extends Dialect {
 		final JdbcTypeRegistry jdbcTypeRegistry = typeContributions.getTypeConfiguration()
 				.getJdbcTypeRegistry();
 
-		if ( getMySQLVersion().isSameOrAfter( 5, 7 ) ) {
 		jdbcTypeRegistry.addDescriptorIfAbsent( SqlTypes.JSON, JsonJdbcType.INSTANCE );
-		}
 
 		// MySQL requires a custom binder for binding untyped nulls with the NULL type
 		typeContributions.contributeJdbcType( NullJdbcType.INSTANCE );
@@ -595,7 +585,7 @@ public class MySQLDialect extends Dialect {
 	 */
 	@Override
 	public String currentTimestamp() {
-		return getMySQLVersion().isBefore( 5, 7 ) ? super.currentTimestamp() : "current_timestamp(6)";
+		return "current_timestamp(6)";
 	}
 
 	// for consistency, we could do this: but I decided not to
@@ -675,7 +665,7 @@ public class MySQLDialect extends Dialect {
 
 	@Override
 	public boolean supportsUnionAll() {
-		return getMySQLVersion().isSameOrAfter( 5 );
+		return true;
 	}
 
 	@Override
@@ -690,9 +680,7 @@ public class MySQLDialect extends Dialect {
 
 	@Override
 	public String getQueryHintString(String query, String hints) {
-		return getMySQLVersion().isBefore( 5 )
+		return IndexQueryHintHandler.INSTANCE.addQueryHints( query, hints );
-				? super.getQueryHintString( query, hints )
-				: IndexQueryHintHandler.INSTANCE.addQueryHints( query, hints );
 	}
 
 	/**
@@ -704,7 +692,7 @@ public class MySQLDialect extends Dialect {
 	}
 
 	public ViolatedConstraintNameExtractor getViolatedConstraintNameExtractor() {
-		return getMySQLVersion().isBefore( 5 ) ? super.getViolatedConstraintNameExtractor() : EXTRACTOR;
+		return EXTRACTOR;
 	}
 
 	private static final ViolatedConstraintNameExtractor EXTRACTOR =
@@ -1005,8 +993,7 @@ public class MySQLDialect extends Dialect {
 
 	@Override
 	public String getTableTypeString() {
-		String engineKeyword = getMySQLVersion().isBefore( 5 ) ? "type" : "engine";
+		return storageEngine.getTableTypeString( "engine" );
-		return storageEngine.getTableTypeString( engineKeyword );
 	}
 
 	@Override
@@ -1020,7 +1007,7 @@ public class MySQLDialect extends Dialect {
 	}
 
 	protected MySQLStorageEngine getDefaultMySQLStorageEngine() {
-		return getMySQLVersion().isBefore( 5, 5 ) ? MyISAMStorageEngine.INSTANCE : InnoDBStorageEngine.INSTANCE;
+		return InnoDBStorageEngine.INSTANCE;
 	}
 
 	@Override

hibernate-core/src/main/java/org/hibernate/dialect/MySQLSqlAstTranslator.java

@@ -141,7 +141,7 @@ public class MySQLSqlAstTranslator<T extends JdbcOperation> extends AbstractSqlA
 
 	@Override
 	public boolean supportsRowValueConstructorSyntaxInInList() {
-		return getDialect().getVersion().isSameOrAfter( 5, 7 );
+		return true;
 	}
 
 	@Override

hibernate-core/src/test/java/org/hibernate/orm/test/dialect/unit/lockhint/MySQLStorageEngineTest.java

@@ -8,16 +8,13 @@ package org.hibernate.orm.test.dialect.unit.lockhint;
 
 import org.hibernate.cfg.AvailableSettings;
 import org.hibernate.cfg.Environment;
-import org.hibernate.dialect.MySQL57Dialect;
+import org.hibernate.dialect.MySQLDialect;
 
 import org.hibernate.testing.junit4.BaseUnitTestCase;
 import org.junit.Test;
 
-import static org.hamcrest.CoreMatchers.nullValue;
-import static org.hamcrest.core.Is.is;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertThat;
 
 import java.lang.reflect.Field;
 import java.util.Properties;
@@ -26,7 +23,7 @@ public class MySQLStorageEngineTest extends BaseUnitTestCase {
 
 	@Test
 	public void testDefaultStorage() {
-		assertEquals( " engine=InnoDB", new MySQL57Dialect().getTableTypeString() );
+		assertEquals( " engine=InnoDB", new MySQLDialect().getTableTypeString() );
 	}
 
 	@Test
@@ -37,7 +34,7 @@ public class MySQLStorageEngineTest extends BaseUnitTestCase {
 		assertNotNull( systemProperties );
 		final Object previousValue = systemProperties.setProperty( AvailableSettings.STORAGE_ENGINE, "myisam" );
 		try {
-			assertEquals( " engine=MyISAM", new MySQL57Dialect().getTableTypeString() );
+			assertEquals( " engine=MyISAM", new MySQLDialect().getTableTypeString() );
 		}
 		finally {
 			if ( previousValue != null ) {

hibernate-core/src/test/java/org/hibernate/orm/test/temporal/MySQLTimestampFspFunctionTest.java

@@ -27,11 +27,11 @@ import static org.junit.Assert.assertTrue;
  * @author Gail Badner.
  */
 @TestForIssue( jiraKey = "HHH-8401")
-@RequiresDialect( value = MySQLDialect.class, majorVersion = 5, minorVersion = 7)
+@RequiresDialect( value = MySQLDialect.class)
 @ServiceRegistry
 @DomainModel
 @SessionFactory
-public class MySQL57TimestampFspFunctionTest {
+public class MySQLTimestampFspFunctionTest {
 
 	@Test
 	public void testTimeStampFunctions(SessionFactoryScope scope) {

hibernate-core/src/test/java/org/hibernate/orm/test/temporal/MySQLTimestampPropertyTest.java

@@ -36,13 +36,13 @@ import static org.junit.jupiter.api.Assertions.assertNotNull;
 /**
  * @author Gail Badner
  */
-@RequiresDialect(value = MySQLDialect.class, majorVersion = 5, minorVersion = 7)
+@RequiresDialect(value = MySQLDialect.class)
 @TestForIssue(jiraKey = "HHH-8401")
 @DomainModel(
-		annotatedClasses = MySQL57TimestampPropertyTest.Entity.class
+		annotatedClasses = MySQLTimestampPropertyTest.Entity.class
 )
 @SessionFactory
-public class MySQL57TimestampPropertyTest {
+public class MySQLTimestampPropertyTest {
 	private final DateFormat timestampFormat = new SimpleDateFormat( "HH:mm:ss.SSS" );
 
 	@Test