Fix derived queries with boolean literals.

`IsTrue` and `IsFalse` queries no longer use a literal in the query, but a bind parameter.
This allows Spring Data JDBC or the JDBC driver to convert the passed boolean value to whatever is required in the database.

For Oracle converter where added to support storing and loading booleans as NUMBER(1,0) where 0 is false and everything else is true.

Closes #908
Original pull request #983

Author: schauder

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/repository/query/QueryMapper.java

@@ -402,11 +402,15 @@ private Condition createCondition(Column column, @Nullable Object mappedValue, i
 		}
 
 		if (comparator == Comparator.IS_TRUE) {
-			return column.isEqualTo(SQL.literalOf(true));
+
+			Expression bind = bindBoolean(column, parameterSource, true);
+			return column.isEqualTo(bind);
 		}
 
 		if (comparator == Comparator.IS_FALSE) {
-			return column.isEqualTo(SQL.literalOf(false));
+
+			Expression bind = bindBoolean(column, parameterSource, false);
+			return column.isEqualTo(bind);
 		}
 
 		Expression columnExpression = column;
@@ -495,6 +499,12 @@ private Condition createCondition(Column column, @Nullable Object mappedValue, i
 		}
 	}
 
+	private Expression bindBoolean(Column column, MapSqlParameterSource parameterSource, boolean value) {
+
+		Object converted = converter.writeValue(value, ClassTypeInformation.OBJECT);
+		return bind(converted, Types.BIT, parameterSource, column.getName().getReference());
+	}
+
 	Field createPropertyField(@Nullable RelationalPersistentEntity<?> entity, SqlIdentifier key) {
 		return entity == null ? new Field(key) : new MetadataBackedField(key, entity, mappingContext, converter);
 	}

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/repository/JdbcRepositoryIntegrationTests.java

@@ -492,6 +492,19 @@ public void pageQueryProjectionShouldReturnProjectedEntities() {
 		assertThat(result.getContent().get(0).getName()).isEqualTo("Entity Name");
 	}
 
+	@Test // #908
+	void derivedQueryWithBooleanLiteralFindsCorrectValues() {
+
+		repository.save(createDummyEntity());
+		DummyEntity entity = createDummyEntity();
+		entity.flag = true;
+		entity = repository.save(entity);
+
+		List<DummyEntity> result = repository.findByFlagTrue();
+
+		assertThat(result).extracting(e -> e.idProp).containsExactly(entity.idProp);
+	}
+
 	private Instant createDummyBeforeAndAfterNow() {
 
 		Instant now = Instant.now();
@@ -557,6 +570,8 @@ interface DummyEntityRepository extends CrudRepository<DummyEntity, Long> {
 
 		@Query("SELECT * FROM DUMMY_ENTITY WHERE OFFSET_DATE_TIME > :threshhold")
 		List<DummyEntity> findByOffsetDateTime(@Param("threshhold") OffsetDateTime threshhold);
+
+		List<DummyEntity> findByFlagTrue();
 	}
 
 	@Configuration
@@ -603,10 +618,12 @@ public void onApplicationEvent(AbstractRelationalEvent<?> event) {
 	@Data
 	@NoArgsConstructor
 	static class DummyEntity {
+
 		String name;
 		Instant pointInTime;
 		OffsetDateTime offsetDateTime;
 		@Id private Long idProp;
+		boolean flag;
 
 		public DummyEntity(String name) {
 			this.name = name;

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/repository/query/PartTreeJdbcQueryUnitTests.java

@@ -27,6 +27,7 @@
 import java.util.List;
 import java.util.Properties;
 
+import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.junit.jupiter.MockitoExtension;
@@ -457,7 +458,7 @@ public void createsQueryToFindAllEntitiesByBooleanAttributeTrue() throws Excepti
 		RelationalParametersParameterAccessor accessor = getAccessor(queryMethod, new Object[0]);
 		ParametrizedQuery query = jdbcQuery.createQuery(accessor, returnedType);
 
-		assertThat(query.getQuery()).isEqualTo(BASE_SELECT + " WHERE " + TABLE + ".\"ACTIVE\" = TRUE");
+		assertThat(query.getQuery()).isEqualTo(BASE_SELECT + " WHERE " + TABLE + ".\"ACTIVE\" = :active");
 	}
 
 	@Test // DATAJDBC-318
@@ -468,7 +469,7 @@ public void createsQueryToFindAllEntitiesByBooleanAttributeFalse() throws Except
 		RelationalParametersParameterAccessor accessor = getAccessor(queryMethod, new Object[0]);
 		ParametrizedQuery query = jdbcQuery.createQuery(accessor, returnedType);
 
-		assertThat(query.getQuery()).isEqualTo(BASE_SELECT + " WHERE " + TABLE + ".\"ACTIVE\" = FALSE");
+		assertThat(query.getQuery()).isEqualTo(BASE_SELECT + " WHERE " + TABLE + ".\"ACTIVE\" = :active");
 	}
 
 	@Test // DATAJDBC-318

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.repository/JdbcRepositoryIntegrationTests-db2.sql

@@ -5,5 +5,6 @@ CREATE TABLE dummy_entity
     id_Prop BIGINT GENERATED BY DEFAULT AS IDENTITY ( START WITH 1 ) PRIMARY KEY,
     NAME    VARCHAR(100),
     POINT_IN_TIME TIMESTAMP,
-    OFFSET_DATE_TIME TIMESTAMP -- with time zone is only supported with z/OS
+    OFFSET_DATE_TIME TIMESTAMP, -- with time zone is only supported with z/OS
+    FLAG BOOLEAN
 );

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.repository/JdbcRepositoryIntegrationTests-h2.sql

@@ -3,5 +3,6 @@ CREATE TABLE dummy_entity
     id_Prop BIGINT GENERATED BY DEFAULT AS IDENTITY ( START WITH 1 ) PRIMARY KEY,
     NAME    VARCHAR(100),
     POINT_IN_TIME TIMESTAMP,
-    OFFSET_DATE_TIME TIMESTAMP WITH TIME ZONE
+    OFFSET_DATE_TIME TIMESTAMP WITH TIME ZONE,
+    FLAG BOOLEAN
 );

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.repository/JdbcRepositoryIntegrationTests-hsql.sql

@@ -3,5 +3,6 @@ CREATE TABLE dummy_entity
     id_Prop BIGINT GENERATED BY DEFAULT AS IDENTITY ( START WITH 1 ) PRIMARY KEY,
     NAME    VARCHAR(100),
     POINT_IN_TIME TIMESTAMP,
-    OFFSET_DATE_TIME TIMESTAMP WITH TIME ZONE
+    OFFSET_DATE_TIME TIMESTAMP WITH TIME ZONE,
+    FLAG BOOLEAN
 );

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.repository/JdbcRepositoryIntegrationTests-mariadb.sql

@@ -3,5 +3,6 @@ CREATE TABLE dummy_entity
     id_Prop BIGINT AUTO_INCREMENT PRIMARY KEY,
     NAME    VARCHAR(100),
     POINT_IN_TIME TIMESTAMP(3),
-    OFFSET_DATE_TIME TIMESTAMP(3)
+    OFFSET_DATE_TIME TIMESTAMP(3),
+    FLAG BOOLEAN
 );

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.repository/JdbcRepositoryIntegrationTests-mssql.sql

@@ -4,5 +4,6 @@ CREATE TABLE dummy_entity
     id_Prop BIGINT IDENTITY PRIMARY KEY,
     NAME    VARCHAR(100),
     POINT_IN_TIME DATETIME,
-    OFFSET_DATE_TIME DATETIMEOFFSET
+    OFFSET_DATE_TIME DATETIMEOFFSET,
+    FLAG BIT
 );

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.repository/JdbcRepositoryIntegrationTests-mysql.sql

@@ -1,9 +1,10 @@
 SET SQL_MODE='ALLOW_INVALID_DATES';
 
-CREATE TABLE dummy_entity
+CREATE TABLE DUMMY_ENTITY
 (
-    id_Prop BIGINT AUTO_INCREMENT PRIMARY KEY,
+    ID_PROP BIGINT AUTO_INCREMENT PRIMARY KEY,
     NAME    VARCHAR(100),
-    POINT_IN_TIME TIMESTAMP(3) default null,
-    OFFSET_DATE_TIME TIMESTAMP(3) default null
+    POINT_IN_TIME TIMESTAMP(3) DEFAULT NULL,
+    OFFSET_DATE_TIME TIMESTAMP(3) DEFAULT NULL,
+    FLAG BIT(1)
 );

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.repository/JdbcRepositoryIntegrationTests-oracle.sql

@@ -5,5 +5,6 @@ CREATE TABLE DUMMY_ENTITY
     ID_PROP NUMBER GENERATED BY DEFAULT ON NULL AS IDENTITY PRIMARY KEY,
     NAME    VARCHAR2(100),
     POINT_IN_TIME TIMESTAMP,
-    OFFSET_DATE_TIME TIMESTAMP WITH TIME ZONE
+    OFFSET_DATE_TIME TIMESTAMP WITH TIME ZONE,
+    FLAG NUMBER(1,0)
 );

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.repository/JdbcRepositoryIntegrationTests-postgres.sql

@@ -4,5 +4,6 @@ CREATE TABLE dummy_entity
     id_Prop SERIAL PRIMARY KEY,
     NAME    VARCHAR(100),
     POINT_IN_TIME TIMESTAMP,
-    OFFSET_DATE_TIME TIMESTAMP WITH TIME ZONE
+    OFFSET_DATE_TIME TIMESTAMP WITH TIME ZONE,
+    FLAG BOOLEAN
 );

spring-data-relational/src/main/java/org/springframework/data/relational/core/dialect/OracleDialect.java

@@ -15,9 +15,15 @@
  */
 package org.springframework.data.relational.core.dialect;
 
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.data.convert.ReadingConverter;
+import org.springframework.data.convert.WritingConverter;
+
 import java.util.Collection;
 import java.util.Collections;
 
+import static java.util.Arrays.*;
+
 /**
  * An SQL dialect for Oracle.
  *
@@ -47,7 +53,25 @@ public IdGeneration getIdGeneration() {
 
 	@Override
 	public Collection<Object> getConverters() {
-		return Collections.singletonList(TimestampAtUtcToOffsetDateTimeConverter.INSTANCE);
+		return asList(TimestampAtUtcToOffsetDateTimeConverter.INSTANCE, NumberToBooleanConverter.INSTANCE, BooleanToIntegerConverter.INSTANCE);
+	}
+
+	@ReadingConverter
+	enum NumberToBooleanConverter implements Converter<Number, Boolean> {
+		INSTANCE;
+
+		@Override
+		public Boolean convert(Number number) {
+			return number.intValue() != 0;
+		}
 	}
+	@WritingConverter
+	enum BooleanToIntegerConverter implements Converter<Boolean, Integer> {
+		INSTANCE;
 
+		@Override
+		public Integer convert(Boolean bool) {
+			return bool ? 1 : 0;
+		}
+	}
 }