HHH-15489 - Remove support for Oracle versions older than 11.2

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

documentation/src/test/java/org/hibernate/userguide/locking/ExplicitLockingTest.java

@@ -147,7 +147,7 @@ public class ExplicitLockingTest {
 	}
 
 	@Test
-	@RequiresDialect(value = OracleDialect.class, majorVersion = 8)
+	@RequiresDialect(value = OracleDialect.class)
 	public void testFollowOnLocking(EntityManagerFactoryScope scope) {
 		scope.inTransaction( entityManager -> {
 			log.info("testBuildLockRequest");

documentation/src/test/java/org/hibernate/userguide/mapping/identifier/RowIdTest.java

@@ -21,7 +21,7 @@ import org.junit.jupiter.api.Test;
 /**
  * @author Vlad Mihalcea
  */
-@RequiresDialect(value = OracleDialect.class, majorVersion = 8)
+@RequiresDialect(value = OracleDialect.class)
 @Jpa(
 		annotatedClasses = RowIdTest.Product.class
 )

documentation/src/test/java/org/hibernate/userguide/sql/OracleCustomSQLWithStoredProcedureTest.java

@@ -34,7 +34,7 @@ import static org.junit.jupiter.api.Assertions.assertNull;
 /**
  * @author Vlad Mihalcea
  */
-@RequiresDialect(value = OracleDialect.class, majorVersion = 8)
+@RequiresDialect(value = OracleDialect.class)
 @Jpa(
 		annotatedClasses = OracleCustomSQLWithStoredProcedureTest.Person.class
 )

documentation/src/test/java/org/hibernate/userguide/sql/OracleStoredProcedureTest.java

@@ -38,7 +38,7 @@ import static org.junit.jupiter.api.Assertions.assertNotNull;
 /**
  * @author Vlad Mihalcea
  */
-@RequiresDialect(value = OracleDialect.class, majorVersion = 8)
+@RequiresDialect(value = OracleDialect.class)
 @Jpa(
         annotatedClasses = {
                 Person.class,

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

@@ -0,0 +1,501 @@
+/*
+ * 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 java.util.List;
+
+import org.hibernate.engine.spi.SessionFactoryImplementor;
+import org.hibernate.internal.util.collections.Stack;
+import org.hibernate.metamodel.mapping.JdbcMappingContainer;
+import org.hibernate.query.IllegalQueryOperationException;
+import org.hibernate.query.sqm.BinaryArithmeticOperator;
+import org.hibernate.query.sqm.ComparisonOperator;
+import org.hibernate.query.sqm.FetchClauseType;
+import org.hibernate.query.sqm.FrameExclusion;
+import org.hibernate.query.sqm.FrameKind;
+import org.hibernate.sql.ast.Clause;
+import org.hibernate.sql.ast.spi.AbstractSqlAstTranslator;
+import org.hibernate.sql.ast.spi.SqlSelection;
+import org.hibernate.sql.ast.tree.Statement;
+import org.hibernate.sql.ast.tree.expression.BinaryArithmeticExpression;
+import org.hibernate.sql.ast.tree.expression.CaseSearchedExpression;
+import org.hibernate.sql.ast.tree.expression.Expression;
+import org.hibernate.sql.ast.tree.expression.FunctionExpression;
+import org.hibernate.sql.ast.tree.expression.Literal;
+import org.hibernate.sql.ast.tree.expression.Over;
+import org.hibernate.sql.ast.tree.expression.SqlTuple;
+import org.hibernate.sql.ast.tree.expression.Summarization;
+import org.hibernate.sql.ast.tree.from.FunctionTableReference;
+import org.hibernate.sql.ast.tree.from.QueryPartTableReference;
+import org.hibernate.sql.ast.tree.from.UnionTableGroup;
+import org.hibernate.sql.ast.tree.from.ValuesTableReference;
+import org.hibernate.sql.ast.tree.insert.InsertStatement;
+import org.hibernate.sql.ast.tree.insert.Values;
+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.ast.tree.select.SelectClause;
+import org.hibernate.sql.ast.tree.select.SortSpecification;
+import org.hibernate.sql.exec.spi.JdbcOperation;
+import org.hibernate.type.SqlTypes;
+
+/**
+ * A SQL AST translator for Oracle.
+ *
+ * @author Christian Beikov
+ */
+public class OracleLegacySqlAstTranslator<T extends JdbcOperation> extends AbstractSqlAstTranslator<T> {
+
+	public OracleLegacySqlAstTranslator(SessionFactoryImplementor sessionFactory, Statement statement) {
+		super( sessionFactory, statement );
+	}
+
+	@Override
+	protected LockStrategy determineLockingStrategy(
+			QuerySpec querySpec,
+			ForUpdateClause forUpdateClause,
+			Boolean followOnLocking) {
+		LockStrategy strategy = super.determineLockingStrategy( querySpec, forUpdateClause, followOnLocking );
+		final boolean followOnLockingDisabled = Boolean.FALSE.equals( followOnLocking );
+		if ( strategy != LockStrategy.FOLLOW_ON && querySpec.hasSortSpecifications() ) {
+			if ( followOnLockingDisabled ) {
+				throw new IllegalQueryOperationException( "Locking with ORDER BY is not supported" );
+			}
+			strategy = LockStrategy.FOLLOW_ON;
+		}
+		// Oracle also doesn't support locks with set operators
+		// See https://docs.oracle.com/cd/B19306_01/server.102/b14200/statements_10002.htm#i2066346
+		if ( strategy != LockStrategy.FOLLOW_ON && isPartOfQueryGroup() ) {
+			if ( followOnLockingDisabled ) {
+				throw new IllegalQueryOperationException( "Locking with set operators is not supported" );
+			}
+			strategy = LockStrategy.FOLLOW_ON;
+		}
+		if ( strategy != LockStrategy.FOLLOW_ON && hasSetOperations( querySpec ) ) {
+			if ( followOnLockingDisabled ) {
+				throw new IllegalQueryOperationException( "Locking with set operators is not supported" );
+			}
+			strategy = LockStrategy.FOLLOW_ON;
+		}
+		if ( strategy != LockStrategy.FOLLOW_ON && useOffsetFetchClause( querySpec ) && !isRowsOnlyFetchClauseType( querySpec ) ) {
+			if ( followOnLockingDisabled ) {
+				throw new IllegalQueryOperationException( "Locking with FETCH is not supported" );
+			}
+			strategy = LockStrategy.FOLLOW_ON;
+		}
+		if ( strategy != LockStrategy.FOLLOW_ON ) {
+			final boolean hasOffset;
+			if ( querySpec.isRoot() && hasLimit() && getLimit().getFirstRow() != null ) {
+				hasOffset = true;
+				// We must record that the generated SQL depends on the fact that there is an offset
+				addAppliedParameterBinding( getOffsetParameter(), null );
+			}
+			else {
+				hasOffset = querySpec.getOffsetClauseExpression() != null;
+			}
+			if ( hasOffset ) {
+				if ( followOnLockingDisabled ) {
+					throw new IllegalQueryOperationException( "Locking with OFFSET is not supported" );
+				}
+				strategy = LockStrategy.FOLLOW_ON;
+			}
+		}
+		return strategy;
+	}
+
+	private boolean hasSetOperations(QuerySpec querySpec) {
+		return querySpec.getFromClause().queryTableGroups( group -> group instanceof UnionTableGroup ? group : null ) != null;
+	}
+
+	private boolean isPartOfQueryGroup() {
+		return getQueryPartStack().findCurrentFirst( part -> part instanceof QueryGroup ? part : null ) != null;
+	}
+
+	protected boolean shouldEmulateFetchClause(QueryPart queryPart) {
+		// Check if current query part is already row numbering to avoid infinite recursion
+		if (getQueryPartForRowNumbering() == queryPart) {
+			return false;
+		}
+		final boolean hasLimit = queryPart.isRoot() && hasLimit() || queryPart.getFetchClauseExpression() != null
+				|| queryPart.getOffsetClauseExpression() != null;
+		if ( !hasLimit ) {
+			return false;
+		}
+		// Even if Oracle supports the OFFSET/FETCH clause, there are conditions where we still want to use the ROWNUM pagination
+		if ( supportsOffsetFetchClause() ) {
+			// When the query has no sort specifications and offset, we want to use the ROWNUM pagination as that is a special locking case
+			return !queryPart.hasSortSpecifications() && !hasOffset( queryPart )
+					// Workaround an Oracle bug, segmentation fault for insert queries with a plain query group and fetch clause
+					|| queryPart instanceof QueryGroup && getClauseStack().isEmpty() && getStatement() instanceof InsertStatement;
+		}
+		return true;
+	}
+
+	@Override
+	protected FetchClauseType getFetchClauseTypeForRowNumbering(QueryPart queryPart) {
+		final FetchClauseType fetchClauseType = super.getFetchClauseTypeForRowNumbering( queryPart );
+		final boolean hasOffset;
+		if ( queryPart.isRoot() && hasLimit() ) {
+			hasOffset = getLimit().getFirstRow() != null;
+		}
+		else {
+			hasOffset = queryPart.getOffsetClauseExpression() != null;
+		}
+		if ( queryPart instanceof QuerySpec && !hasOffset && fetchClauseType == FetchClauseType.ROWS_ONLY ) {
+			// We return null here, because in this particular case, we render a special rownum query
+			// which can be seen in #emulateFetchOffsetWithWindowFunctions
+			// Note that we also build upon this in #visitOrderBy
+			return null;
+		}
+		return fetchClauseType;
+	}
+
+	@Override
+	protected void emulateFetchOffsetWithWindowFunctions(
+			QueryPart queryPart,
+			Expression offsetExpression,
+			Expression fetchExpression,
+			FetchClauseType fetchClauseType,
+			boolean emulateFetchClause) {
+		if ( queryPart instanceof QuerySpec && offsetExpression == null && fetchClauseType == FetchClauseType.ROWS_ONLY ) {
+			// Special case for Oracle to support locking along with simple max results paging
+			final QuerySpec querySpec = (QuerySpec) queryPart;
+			withRowNumbering(
+					querySpec,
+					true, // we need select aliases to avoid ORA-00918: column ambiguously defined
+					() -> {
+						final QueryPart currentQueryPart = getQueryPartStack().getCurrent();
+						final boolean needsParenthesis;
+						final boolean needsWrapper;
+						if ( currentQueryPart instanceof QueryGroup ) {
+							needsParenthesis = false;
+							// visitQuerySpec will add the select wrapper
+							needsWrapper = !currentQueryPart.hasOffsetOrFetchClause();
+						}
+						else {
+							needsParenthesis = !querySpec.isRoot();
+							needsWrapper = true;
+						}
+						if ( needsWrapper ) {
+							if ( needsParenthesis ) {
+								appendSql( '(' );
+							}
+							appendSql( "select * from " );
+							if ( !needsParenthesis ) {
+								appendSql( '(' );
+							}
+						}
+						super.visitQuerySpec( querySpec );
+						if ( needsWrapper ) {
+							if ( !needsParenthesis ) {
+								appendSql( ')' );
+							}
+						}
+						appendSql( " where rownum<=" );
+						final Stack<Clause> clauseStack = getClauseStack();
+						clauseStack.push( Clause.WHERE );
+						try {
+							fetchExpression.accept( this );
+
+							// We render the FOR UPDATE clause in the outer query
+							clauseStack.pop();
+							clauseStack.push( Clause.FOR_UPDATE );
+							visitForUpdateClause( querySpec );
+						}
+						finally {
+							clauseStack.pop();
+						}
+
+						if ( needsWrapper ) {
+							if ( needsParenthesis ) {
+								appendSql( ')' );
+							}
+						}
+					}
+			);
+		}
+		else {
+			super.emulateFetchOffsetWithWindowFunctions(
+					queryPart,
+					offsetExpression,
+					fetchExpression,
+					fetchClauseType,
+					emulateFetchClause
+			);
+		}
+	}
+
+	@Override
+	protected void visitOrderBy(List<SortSpecification> sortSpecifications) {
+		// If we have a query part for row numbering, there is no need to render the order by clause
+		// as that is part of the row numbering window function already, by which we then order by in the outer query
+		final QueryPart queryPartForRowNumbering = getQueryPartForRowNumbering();
+		if ( queryPartForRowNumbering == null ) {
+			renderOrderBy( true, sortSpecifications );
+		}
+		else {
+			// This logic is tightly coupled to #emulateFetchOffsetWithWindowFunctions and #getFetchClauseTypeForRowNumbering
+			// so that this is rendered when we end up in the special case for Oracle that renders a rownum filter
+			if ( getFetchClauseTypeForRowNumbering( queryPartForRowNumbering ) == null ) {
+				final QuerySpec querySpec = (QuerySpec) queryPartForRowNumbering;
+				if ( querySpec.getOffsetClauseExpression() == null
+						&& ( !querySpec.isRoot() || getOffsetParameter() == null ) ) {
+					// When rendering `rownum` for Oracle, we need to render the order by clause still
+					renderOrderBy( true, sortSpecifications );
+				}
+			}
+		}
+	}
+
+	@Override
+	protected void visitValuesList(List<Values> valuesList) {
+		if ( valuesList.size() < 2 ) {
+			super.visitValuesList( valuesList );
+		}
+		else {
+			// Oracle doesn't support a multi-values insert
+			// So we render a select union emulation instead
+			String separator = "";
+			final Stack<Clause> clauseStack = getClauseStack();
+			try {
+				clauseStack.push( Clause.VALUES );
+				for ( Values values : valuesList ) {
+					appendSql( separator );
+					renderExpressionsAsSubquery( values.getExpressions() );
+					separator = " union all ";
+				}
+			}
+			finally {
+				clauseStack.pop();
+			}
+		}
+	}
+
+	@Override
+	public void visitValuesTableReference(ValuesTableReference tableReference) {
+		emulateValuesTableReferenceColumnAliasing( tableReference );
+	}
+
+	@Override
+	public void visitQueryPartTableReference(QueryPartTableReference tableReference) {
+		emulateQueryPartTableReferenceColumnAliasing( tableReference );
+	}
+
+	@Override
+	public void visitFunctionTableReference(FunctionTableReference tableReference) {
+		append( "table(" );
+		tableReference.getFunctionExpression().accept( this );
+		append( CLOSE_PARENTHESIS );
+		renderTableReferenceIdentificationVariable( tableReference );
+	}
+
+	@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 visitOffsetFetchClause(QueryPart queryPart) {
+		if ( !isRowNumberingCurrentQueryPart() ) {
+			if ( supportsOffsetFetchClause() ) {
+				renderOffsetFetchClause( queryPart, true );
+			}
+			else {
+				assertRowsOnlyFetchClauseType( queryPart );
+			}
+		}
+	}
+
+	@Override
+	protected void renderRowNumber(SelectClause selectClause, QueryPart queryPart) {
+		if ( !queryPart.hasSortSpecifications() ) {
+			// Oracle doesn't allow an empty over clause for the row_number() function
+			appendSql( "rownum" );
+		}
+		else {
+			super.renderRowNumber( selectClause, queryPart );
+		}
+	}
+
+	@Override
+	public void visitOver(Over<?> over) {
+		final Expression expression = over.getExpression();
+		if ( expression instanceof FunctionExpression && "row_number".equals( ( (FunctionExpression) expression ).getFunctionName() ) ) {
+			if ( over.getPartitions().isEmpty() && over.getOrderList().isEmpty()
+					&& over.getStartKind() == FrameKind.UNBOUNDED_PRECEDING
+					&& over.getEndKind() == FrameKind.CURRENT_ROW
+					&& over.getExclusion() == FrameExclusion.NO_OTHERS ) {
+				// Oracle doesn't allow an empty over clause for the row_number() function
+				append( "rownum" );
+				return;
+			}
+		}
+		super.visitOver( over );
+	}
+
+	@Override
+	protected void renderComparison(Expression lhs, ComparisonOperator operator, Expression rhs) {
+		final JdbcMappingContainer lhsExpressionType = lhs.getExpressionType();
+		if ( lhsExpressionType == null ) {
+			renderComparisonEmulateDecode( lhs, operator, rhs );
+			return;
+		}
+		switch ( lhsExpressionType.getJdbcMappings().get( 0 ).getJdbcType().getJdbcTypeCode() ) {
+			case SqlTypes.SQLXML:
+				// In Oracle, XMLTYPE is not "comparable", so we have to use the xmldiff function for this purpose
+				switch ( operator ) {
+					case EQUAL:
+					case NOT_DISTINCT_FROM:
+						appendSql( "0=" );
+						break;
+					case NOT_EQUAL:
+					case DISTINCT_FROM:
+						appendSql( "1=" );
+						break;
+					default:
+						renderComparisonEmulateDecode( lhs, operator, rhs );
+						return;
+				}
+				appendSql( "existsnode(xmldiff(" );
+				lhs.accept( this );
+				appendSql( ',' );
+				rhs.accept( this );
+				appendSql( "),'/*[local-name()=''xdiff'']/*')" );
+				break;
+			case SqlTypes.BLOB:
+				// In Oracle, BLOB types are not "comparable", so we have to use the dbms_lob.compare function for this purpose
+				switch ( operator ) {
+					case EQUAL:
+						appendSql( "0=" );
+						break;
+					case NOT_EQUAL:
+						appendSql( "-1=" );
+						break;
+					default:
+						renderComparisonEmulateDecode( lhs, operator, rhs );
+						return;
+				}
+				appendSql( "dbms_lob.compare(" );
+				lhs.accept( this );
+				appendSql( ',' );
+				rhs.accept( this );
+				appendSql( ')' );
+				break;
+			default:
+				renderComparisonEmulateDecode( lhs, operator, rhs );
+				break;
+		}
+	}
+
+	@Override
+	protected void renderSelectTupleComparison(
+			List<SqlSelection> lhsExpressions,
+			SqlTuple tuple,
+			ComparisonOperator operator) {
+		emulateSelectTupleComparison( lhsExpressions, tuple.getExpressions(), operator, true );
+	}
+
+	@Override
+	protected void visitCaseSearchedExpression(CaseSearchedExpression caseSearchedExpression, boolean inSelect) {
+		// Oracle did not add support for CASE until 9i
+		if ( getDialect().getVersion().isBefore( 9 ) ) {
+			visitDecodeCaseSearchedExpression( caseSearchedExpression );
+		}
+		else {
+			super.visitCaseSearchedExpression( caseSearchedExpression, inSelect );
+		}
+	}
+
+	@Override
+	protected void renderPartitionItem(Expression expression) {
+		if ( expression instanceof Literal ) {
+			appendSql( "()" );
+		}
+		else if ( expression instanceof Summarization ) {
+			Summarization summarization = (Summarization) expression;
+			appendSql( summarization.getKind().sqlText() );
+			appendSql( OPEN_PARENTHESIS );
+			renderCommaSeparated( summarization.getGroupings() );
+			appendSql( CLOSE_PARENTHESIS );
+		}
+		else {
+			expression.accept( this );
+		}
+	}
+
+	@Override
+	protected boolean supportsDuplicateSelectItemsInQueryGroup() {
+		return false;
+	}
+
+	@Override
+	protected boolean supportsRowValueConstructorSyntax() {
+		return false;
+	}
+
+	@Override
+	protected boolean supportsRowValueConstructorSyntaxInInList() {
+		return getDialect().getVersion().isSameOrAfter( 8, 2 );
+	}
+
+	@Override
+	protected boolean supportsRowValueConstructorSyntaxInQuantifiedPredicates() {
+		return false;
+	}
+
+	@Override
+	protected boolean supportsRowValueConstructorSyntaxInInSubQuery() {
+		return getDialect().getVersion().isSameOrAfter( 9 );
+	}
+
+	@Override
+	protected String getFromDual() {
+		return " from dual";
+	}
+
+	@Override
+	protected String getFromDualForSelectOnly() {
+		return getFromDual();
+	}
+
+	private boolean supportsOffsetFetchClause() {
+		return getDialect().supportsFetchClause( FetchClauseType.ROWS_ONLY );
+	}
+
+	@Override
+	public void visitBinaryArithmeticExpression(BinaryArithmeticExpression arithmeticExpression) {
+		final BinaryArithmeticOperator operator = arithmeticExpression.getOperator();
+		if ( operator == BinaryArithmeticOperator.MODULO ) {
+			append( "mod" );
+			appendSql( OPEN_PARENTHESIS );
+			arithmeticExpression.getLeftHandOperand().accept( this );
+			appendSql( ',' );
+			arithmeticExpression.getRightHandOperand().accept( this );
+			appendSql( CLOSE_PARENTHESIS );
+			return;
+		}
+		else {
+			super.visitBinaryArithmeticExpression( arithmeticExpression );
+		}
+	}
+
+}

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

@@ -113,12 +113,14 @@ public class OracleDialect extends Dialect {
 
 	public static final String PREFER_LONG_RAW = "hibernate.dialect.oracle.prefer_long_raw";
 
+	private static final DatabaseVersion MINIMUM_VERSION = DatabaseVersion.make( 11, 2 );
+
 	private final LimitHandler limitHandler = supportsFetchClause( FetchClauseType.ROWS_ONLY )
 			? Oracle12LimitHandler.INSTANCE
 			: new LegacyOracleLimitHandler( getVersion() );
 
 	public OracleDialect() {
-		this( DatabaseVersion.make( 8, 0 ) );
+		this( MINIMUM_VERSION );
 	}
 
 	public OracleDialect(DatabaseVersion version) {
@@ -129,6 +131,11 @@ public class OracleDialect extends Dialect {
 		super(info);
 	}
 
+	@Override
+	protected DatabaseVersion getMinimumSupportedVersion() {
+		return MINIMUM_VERSION;
+	}
+
 	@Override
 	public int getPreferredSqlTypeCodeForBoolean() {
 		return Types.BIT;
@@ -181,13 +188,8 @@ public class OracleDialect extends Dialect {
 		functionFactory.octetLength_pattern( "lengthb(?1)", "dbms_lob.getlength(?1)*2" );
 		functionFactory.bitLength_pattern( "lengthb(?1)*8", "dbms_lob.getlength(?1)*16" );
 
-		if ( getVersion().isBefore( 9 ) ) {
-			queryEngine.getSqmFunctionRegistry().register( "coalesce", new NvlCoalesceEmulation() );
-		}
-		else {
 		//Oracle has had coalesce() since 9.0.1
 		functionFactory.coalesce();
-		}
 
 		queryEngine.getSqmFunctionRegistry().registerBinaryTernaryPattern(
 				"locate",
@@ -240,7 +242,7 @@ public class OracleDialect extends Dialect {
 
 	@Override
 	public String currentDate() {
-		return getVersion().isBefore( 9 ) ? currentTimestamp() : "current_date";
+		return "current_date";
 	}
 
 	@Override
@@ -250,7 +252,7 @@ public class OracleDialect extends Dialect {
 
 	@Override
 	public String currentTimestamp() {
-		return getVersion().isBefore( 9 ) ? "sysdate" : currentTimestampWithTimeZone();
+		return currentTimestampWithTimeZone();
 	}
 
 	@Override
@@ -260,12 +262,12 @@ public class OracleDialect extends Dialect {
 
 	@Override
 	public String currentLocalTimestamp() {
-		return getVersion().isBefore( 9 ) ? currentTimestamp() : "localtimestamp";
+		return "localtimestamp";
 	}
 
 	@Override
 	public String currentTimestampWithTimeZone() {
-		return getVersion().isBefore( 9 ) ? currentTimestamp() : "current_timestamp";
+		return "current_timestamp";
 	}
 
 
@@ -578,15 +580,12 @@ public class OracleDialect extends Dialect {
 			case DATE:
 			case TIME:
 				return "date";
-			case TIMESTAMP:
 				// the only difference between date and timestamp
 				// on Oracle is that date has no fractional seconds
-			case TIMESTAMP_WITH_TIMEZONE:
-				return getVersion().isBefore( 9 ) ? "date" : super.columnType( sqlTypeCode );
 			case TIME_WITH_TIMEZONE:
-				return getVersion().isBefore( 9 ) ? "date" : "timestamp($p) with time zone";
+				return "timestamp($p) with time zone";
 			case VARCHAR:
-				return getVersion().isBefore( 9 ) ? "varchar2($l)" : "varchar2($l char)";
+				return "varchar2($l char)";
 			case NVARCHAR:
 				return "nvarchar2($l)";
 			case BINARY:
@@ -602,21 +601,18 @@ public class OracleDialect extends Dialect {
 		final DdlTypeRegistry ddlTypeRegistry = typeContributions.getTypeConfiguration().getDdlTypeRegistry();
 
 		ddlTypeRegistry.addDescriptor( new DdlTypeImpl( SQLXML, "SYS.XMLTYPE", this ) );
-		if ( getVersion().isSameOrAfter( 10 ) ) {
 		ddlTypeRegistry.addDescriptor( new DdlTypeImpl( GEOMETRY, "MDSYS.SDO_GEOMETRY", this ) );
 	}
-	}
 
 	@Override
 	public TimeZoneSupport getTimeZoneSupport() {
-		return getVersion().isSameOrAfter( 9 ) ? TimeZoneSupport.NATIVE : TimeZoneSupport.NONE;
+		return TimeZoneSupport.NATIVE;
 	}
 
 	@Override
 	protected void initDefaultProperties() {
 		super.initDefaultProperties();
-		String newerVersion = Boolean.toString( getVersion().isSameOrAfter( 12 ) );
+		getDefaultProperties().setProperty( Environment.BATCH_VERSIONED_DATA, Boolean.toString( getVersion().isSameOrAfter( 12 ) ) );
-		getDefaultProperties().setProperty( Environment.BATCH_VERSIONED_DATA, newerVersion );
 	}
 
 	@Override
@@ -764,32 +760,9 @@ public class OracleDialect extends Dialect {
 		return limitHandler;
 	}
 
-	@Override
-	public String getSelectClauseNullString(int sqlType, TypeConfiguration typeConfiguration) {
-		if ( getVersion().isSameOrAfter( 9 ) ) {
-			return super.getSelectClauseNullString( sqlType, typeConfiguration );
-		}
-		else {
-			switch(sqlType) {
-				case Types.VARCHAR:
-				case Types.CHAR:
-					return "to_char(null)";
-				case Types.DATE:
-				case Types.TIME:
-				case Types.TIMESTAMP:
-				case Types.TIMESTAMP_WITH_TIMEZONE:
-					return "to_date(null)";
-				default:
-					return "to_number(null)";
-			}
-		}
-	}
-
 	@Override
 	public String getCurrentTimestampSelectString() {
-		return getVersion().isBefore( 9 )
+		return "select systimestamp from dual";
-				? "select sysdate from dual"
-				: "select systimestamp from dual";
 	}
 
 
@@ -1104,12 +1077,12 @@ public class OracleDialect extends Dialect {
 
 	@Override
 	public boolean supportsNoWait() {
-		return getVersion().isSameOrAfter( 9 );
+		return true;
 	}
 
 	@Override
 	public boolean supportsSkipLocked() {
-		return getVersion().isSameOrAfter( 10 );
+		return true;
 	}
 
 	@Override

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

@@ -414,17 +414,6 @@ public class OracleSqlAstTranslator<T extends JdbcOperation> extends AbstractSql
 		emulateSelectTupleComparison( lhsExpressions, tuple.getExpressions(), operator, true );
 	}
 
-	@Override
-	protected void visitCaseSearchedExpression(CaseSearchedExpression caseSearchedExpression, boolean inSelect) {
-		// Oracle did not add support for CASE until 9i
-		if ( getDialect().getVersion().isBefore( 9 ) ) {
-			visitDecodeCaseSearchedExpression( caseSearchedExpression );
-		}
-		else {
-			super.visitCaseSearchedExpression( caseSearchedExpression, inSelect );
-		}
-	}
-
 	@Override
 	protected void renderPartitionItem(Expression expression) {
 		if ( expression instanceof Literal ) {
@@ -454,7 +443,7 @@ public class OracleSqlAstTranslator<T extends JdbcOperation> extends AbstractSql
 
 	@Override
 	protected boolean supportsRowValueConstructorSyntaxInInList() {
-		return getDialect().getVersion().isSameOrAfter( 8, 2 );
+		return true;
 	}
 
 	@Override
@@ -464,7 +453,7 @@ public class OracleSqlAstTranslator<T extends JdbcOperation> extends AbstractSql
 
 	@Override
 	protected boolean supportsRowValueConstructorSyntaxInInSubQuery() {
-		return getDialect().getVersion().isSameOrAfter( 9 );
+		return true;
 	}
 
 	@Override

hibernate-core/src/test/java/org/hibernate/orm/test/generatedkeys/select/SelectGeneratorTest.java

@@ -24,7 +24,7 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
 		xmlMappings = "org/hibernate/orm/test/generatedkeys/select/MyEntity.hbm.xml"
 )
 @SessionFactory
-@RequiresDialect(value = OracleDialect.class, majorVersion = 9)
+@RequiresDialect(value = OracleDialect.class)
 public class SelectGeneratorTest {
 
 	@Test

hibernate-core/src/test/java/org/hibernate/orm/test/id/array/ByteArrayIdTest.java

@@ -34,7 +34,7 @@ import static org.junit.jupiter.api.Assertions.assertTrue;
  * @author Gail Badner
  */
 @SkipForDialect(dialectClass = MySQLDialect.class, majorVersion = 5, matchSubTypes = true, reason = "BLOB/TEXT column 'id' used in key specification without a key length")
-@SkipForDialect(dialectClass = OracleDialect.class, majorVersion = 9, matchSubTypes = true, reason = "ORA-02329: column of datatype LOB cannot be unique or a primary key")
+@SkipForDialect(dialectClass = OracleDialect.class, matchSubTypes = true, reason = "ORA-02329: column of datatype LOB cannot be unique or a primary key")
 @DomainModel(
 		annotatedClasses = ByteArrayIdTest.DemoEntity.class
 )

hibernate-core/src/test/java/org/hibernate/orm/test/id/array/PrimitiveByteArrayIdTest.java

@@ -34,7 +34,7 @@ import static org.junit.jupiter.api.Assertions.assertTrue;
  * @author Gail Badner
  */
 @SkipForDialect(dialectClass = MySQLDialect.class, majorVersion = 5, reason = "BLOB/TEXT column 'id' used in key specification without a key length")
-@SkipForDialect(dialectClass = OracleDialect.class, majorVersion = 9, matchSubTypes = true, reason = "ORA-02329: column of datatype LOB cannot be unique or a primary key")
+@SkipForDialect(dialectClass = OracleDialect.class, matchSubTypes = true, reason = "ORA-02329: column of datatype LOB cannot be unique or a primary key")
 @DomainModel(
 		annotatedClasses = PrimitiveByteArrayIdTest.DemoEntity.class
 )

hibernate-core/src/test/java/org/hibernate/orm/test/jpa/naturalid/MutableNaturalIdTest.java

@@ -21,7 +21,7 @@ import static org.junit.jupiter.api.Assertions.assertTrue;
 /**
  * @author Steve Ebersole
  */
-@SkipForDialect(dialectClass = OracleDialect.class, majorVersion = 8, matchSubTypes = true,
+@SkipForDialect(dialectClass = OracleDialect.class, matchSubTypes = true,
 		reason = "Oracle do not support identity key generation")
 @SkipForDialect(dialectClass = AbstractHANADialect.class, matchSubTypes = true,
 		reason = "Hana do not support identity key generation")

hibernate-core/src/test/java/org/hibernate/orm/test/mapping/generated/PartiallyGeneratedComponentTest.java

@@ -28,7 +28,7 @@ import static org.junit.jupiter.api.Assertions.assertNotNull;
 		xmlMappings = "org/hibernate/orm/test/mapping/generated/ComponentOwner.hbm.xml"
 )
 @SessionFactory
-@RequiresDialect( value = OracleDialect.class, majorVersion = 9 )
+@RequiresDialect( value = OracleDialect.class )
 public class PartiallyGeneratedComponentTest {
 
 	@Test

hibernate-core/src/test/java/org/hibernate/orm/test/nationalized/StringNationalizedTest.java

@@ -35,7 +35,7 @@ import static org.hamcrest.core.Is.is;
 @TestForIssue(jiraKey = "10495")
 @RequiresDialects(
 		value = {
-				@RequiresDialect(value = OracleDialect.class, majorVersion = 10),
+				@RequiresDialect(value = OracleDialect.class),
 				@RequiresDialect(value = PostgreSQLDialect.class, majorVersion = 8, minorVersion = 1)
 		})
 @DomainModel(

hibernate-core/src/test/java/org/hibernate/orm/test/ops/OracleNoColumnInsertTest.java

@@ -18,7 +18,7 @@ import org.junit.jupiter.api.Test;
 /**
  * @author Vlad Mihalcea
  */
-@RequiresDialect(value = OracleDialect.class, majorVersion = 9)
+@RequiresDialect(value = OracleDialect.class)
 @TestForIssue(jiraKey = "HHH-13104")
 @DomainModel(
 		xmlMappings = "org/hibernate/orm/test/ops/Competition.hbm.xml"

hibernate-core/src/test/java/org/hibernate/orm/test/queryhint/OracleQueryHintTest.java

@@ -39,7 +39,7 @@ import static org.junit.jupiter.api.Assertions.assertTrue;
 /**
  * @author Brett Meyer
  */
-@RequiresDialect(value = OracleDialect.class, majorVersion = 8)
+@RequiresDialect(value = OracleDialect.class)
 @DomainModel(
 		annotatedClasses = { OracleQueryHintTest.Employee.class, OracleQueryHintTest.Department.class }
 )

hibernate-core/src/test/java/org/hibernate/orm/test/rowid/RowIdTest.java

@@ -33,7 +33,7 @@ import static org.junit.Assert.assertThat;
  */
 @DomainModel( annotatedClasses = RowIdTest.Product.class )
 @SessionFactory(statementInspectorClass = SQLStatementInspector.class)
-@RequiresDialect( value = OracleDialect.class, majorVersion = 9)
+@RequiresDialect( value = OracleDialect.class)
 public class RowIdTest {
 
 	@BeforeEach

hibernate-core/src/test/java/org/hibernate/orm/test/rowid/RowIdTest2.java

@@ -26,7 +26,7 @@ import jakarta.persistence.criteria.CriteriaQuery;
 /**
  * @author Gavin King
  */
-@RequiresDialect(value = OracleDialect.class, majorVersion = 9)
+@RequiresDialect(value = OracleDialect.class)
 @DomainModel(
 		xmlMappings = "org/hibernate/orm/test/rowid/Point.hbm.xml"
 )

hibernate-core/src/test/java/org/hibernate/orm/test/schemavalidation/SynonymValidationTest.java

@@ -37,7 +37,7 @@ import org.junit.jupiter.api.Test;
  *
  * @author Brett Meyer
  */
-@RequiresDialect(value = OracleDialect.class, majorVersion = 9)
+@RequiresDialect(value = OracleDialect.class)
 public class SynonymValidationTest extends BaseSessionFactoryFunctionalTest {
 
 	private StandardServiceRegistry ssr;

hibernate-envers/src/main/java/org/hibernate/envers/enhanced/OrderedSequenceStructure.java

@@ -70,7 +70,7 @@ public class OrderedSequenceStructure extends SequenceStructure {
 			);
 
 			//noinspection deprecation
-			if ( dialect instanceof OracleDialect && dialect.getVersion().isSameOrAfter( 8 ) ) {
+			if ( dialect instanceof OracleDialect ) {
 				for ( int i = 0; i < createStrings.length; ++i ) {
 					createStrings[i] = createStrings[i] + ORDER;
 				}

hibernate-envers/src/main/java/org/hibernate/envers/internal/entities/mapper/SinglePropertyMapper.java

@@ -61,7 +61,7 @@ public class SinglePropertyMapper extends AbstractPropertyMapper implements Simp
 		boolean dbLogicallyDifferent = true;
 		final Dialect dialect = session.getFactory().getJdbcServices()
 				.getDialect();
-		if ( ( dialect instanceof OracleDialect && dialect.getVersion().isSameOrAfter( 8 ) ) && (newObj instanceof String || oldObj instanceof String) ) {
+		if ( ( dialect instanceof OracleDialect ) && (newObj instanceof String || oldObj instanceof String) ) {
 			// Don't generate new revision when database replaces empty string with NULL during INSERT or UPDATE statements.
 			dbLogicallyDifferent = !(StringTools.isEmpty( newObj ) && StringTools.isEmpty( oldObj ));
 		}