Add the appropriate SQL type representation for floats in Postgres arrays.

Note that there is a separate problem with loading arrays of floats.

Original pull request #1037
See #1046

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/core/dialect/JdbcPostgresDialect.java

@@ -38,7 +38,15 @@ public class JdbcPostgresDialect extends PostgresDialect implements JdbcDialect
 	static class JdbcPostgresArrayColumns extends PostgresArrayColumns implements JdbcArrayColumns {
 		@Override
 		public String getSqlTypeRepresentation(JDBCType jdbcType) {
-			return jdbcType == JDBCType.DOUBLE ? "FLOAT8" : jdbcType.getName();
+
+			if (jdbcType == JDBCType.DOUBLE) {
+				return "FLOAT8";
+			}
+			if (jdbcType == JDBCType.REAL) {
+				return "FLOAT4";
+			}
+
+			return jdbcType.getName();
 		}
 	}
 }

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/core/JdbcAggregateTemplateIntegrationTests.java

@@ -573,6 +573,25 @@ public class JdbcAggregateTemplateIntegrationTests {
 		assertThat(reloaded.digits).isEqualTo(Arrays.asList(1.2, 1.3, 1.4));
 	}
 
+	@Test // GH-1033
+	@EnabledOnFeature(SUPPORTS_ARRAYS)
+	public void saveAndLoadAnEntityWithListOfFloat() {
+
+		FloatListOwner floatListOwner = new FloatListOwner();
+		final List<Float> values = Arrays.asList(1.2f, 1.3f, 1.4f);
+		floatListOwner.digits.addAll(values);
+
+		FloatListOwner saved = template.save(floatListOwner);
+
+		assertThat(saved.id).isNotNull();
+
+		FloatListOwner reloaded = template.findById(saved.id, FloatListOwner.class);
+
+		assertThat(reloaded).isNotNull();
+		assertThat(reloaded.id).isEqualTo(saved.id);
+
+	}
+
 	@Test // DATAJDBC-259
 	@EnabledOnFeature(SUPPORTS_ARRAYS)
 	public void saveAndLoadAnEntityWithSet() {
@@ -929,6 +948,7 @@ public class JdbcAggregateTemplateIntegrationTests {
 
 		List<String> digits = new ArrayList<>();
 	}
+
 	@Table("ARRAY_OWNER")
 	private static class SetOwner {
 		@Id Long id;
@@ -943,6 +963,13 @@ public class JdbcAggregateTemplateIntegrationTests {
 		List<Double> digits = new ArrayList<>();
 	}
 
+	private static class FloatListOwner {
+
+		@Id Long id;
+
+		List<Float> digits = new ArrayList<>();
+	}
+
 	@Data
 	static class LegoSet {
 

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.core/JdbcAggregateTemplateIntegrationTests-h2.sql

@@ -58,6 +58,12 @@ CREATE TABLE DOUBLE_LIST_OWNER
     DIGITS           ARRAY[10]
 );
 
+CREATE TABLE FLOAT_LIST_OWNER
+(
+    ID               SERIAL PRIMARY KEY,
+    DIGITS           ARRAY[10]
+);
+
 CREATE TABLE CHAIN4
 (
     FOUR       SERIAL PRIMARY KEY,

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.core/JdbcAggregateTemplateIntegrationTests-hsql.sql

@@ -60,6 +60,12 @@ CREATE TABLE DOUBLE_LIST_OWNER
     DIGITS      DOUBLE PRECISION ARRAY[10]
 );
 
+CREATE TABLE FLOAT_LIST_OWNER
+(
+    ID          BIGINT GENERATED BY DEFAULT AS IDENTITY (START WITH 1) PRIMARY KEY,
+    DIGITS      FLOAT ARRAY[10]
+);
+
 CREATE TABLE CHAIN4
 (
   FOUR       BIGINT GENERATED BY DEFAULT AS IDENTITY (START WITH 40) PRIMARY KEY,

spring-data-jdbc/src/test/resources/org.springframework.data.jdbc.core/JdbcAggregateTemplateIntegrationTests-postgres.sql

@@ -67,6 +67,12 @@ CREATE TABLE DOUBLE_LIST_OWNER
     DIGITS           DOUBLE PRECISION[10]
 );
 
+CREATE TABLE FLOAT_LIST_OWNER
+(
+    ID               SERIAL PRIMARY KEY,
+    DIGITS           FLOAT[10]
+);
+
 CREATE TABLE BYTE_ARRAY_OWNER
 (
     ID          SERIAL PRIMARY KEY,