This is an automated email from the ASF dual-hosted git repository.
mmior pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/calcite.git
The following commit(s) were added to refs/heads/master by this push:
new 8eb8520 CALCITE-2856-Emulating Cross Join For SparkSqlDialect
8eb8520 is described below
commit 8eb852039db04c132ae7a99943495f87cf39dfd2
Author: stuti.gupta <[email protected]>
AuthorDate: Mon Feb 18 16:29:59 2019 +0530
CALCITE-2856-Emulating Cross Join For SparkSqlDialect
---
.../calcite/rel/rel2sql/RelToSqlConverter.java | 8 ++-
.../java/org/apache/calcite/sql/SqlDialect.java | 5 ++
.../apache/calcite/sql/SqlDialectFactoryImpl.java | 7 +++
.../calcite/sql/dialect/SparkSqlDialect.java | 60 ++++++++++++++++++++++
.../calcite/rel/rel2sql/RelToSqlConverterTest.java | 12 +++++
5 files changed, 90 insertions(+), 2 deletions(-)
diff --git
a/core/src/main/java/org/apache/calcite/rel/rel2sql/RelToSqlConverter.java
b/core/src/main/java/org/apache/calcite/rel/rel2sql/RelToSqlConverter.java
index 4ee45fd..1e46fd6 100644
--- a/core/src/main/java/org/apache/calcite/rel/rel2sql/RelToSqlConverter.java
+++ b/core/src/main/java/org/apache/calcite/rel/rel2sql/RelToSqlConverter.java
@@ -126,8 +126,8 @@ public class RelToSqlConverter extends SqlImplementor
SqlNode sqlCondition = null;
SqlLiteral condType = JoinConditionType.ON.symbol(POS);
JoinType joinType = joinType(e.getJoinType());
- if (e.getJoinType() == JoinRelType.INNER &&
e.getCondition().isAlwaysTrue()) {
- joinType = JoinType.COMMA;
+ if (isCrossJoin(e)) {
+ joinType = dialect.emulateJoinTypeForCrossJoin();
condType = JoinConditionType.NONE.symbol(POS);
} else {
sqlCondition = convertConditionToSqlNode(e.getCondition(),
@@ -146,6 +146,10 @@ public class RelToSqlConverter extends SqlImplementor
return result(join, leftResult, rightResult);
}
+ private boolean isCrossJoin(final Join e) {
+ return e.getJoinType() == JoinRelType.INNER &&
e.getCondition().isAlwaysTrue();
+ }
+
/** @see #dispatch */
public Result visit(Filter e) {
final RelNode input = e.getInput();
diff --git a/core/src/main/java/org/apache/calcite/sql/SqlDialect.java
b/core/src/main/java/org/apache/calcite/sql/SqlDialect.java
index f4de22d..231a9a4 100644
--- a/core/src/main/java/org/apache/calcite/sql/SqlDialect.java
+++ b/core/src/main/java/org/apache/calcite/sql/SqlDialect.java
@@ -741,6 +741,10 @@ public class SqlDialect {
return null;
}
+ public JoinType emulateJoinTypeForCrossJoin() {
+ return JoinType.COMMA;
+ }
+
protected SqlNode emulateNullDirectionWithIsNull(SqlNode node,
boolean nullsFirst, boolean desc) {
// No need for emulation if the nulls will anyways come out the way we want
@@ -986,6 +990,7 @@ public class SqlDialect {
HSQLDB("Hsqldb", null, NullCollation.HIGH),
VERTICA("Vertica", "\"", NullCollation.HIGH),
SQLSTREAM("SQLstream", "\"", NullCollation.HIGH),
+ SPARK("Spark", null, NullCollation.LOW),
/** Paraccel, now called Actian Matrix. Redshift is based on this, so
* presumably the dialect capabilities are similar. */
diff --git
a/core/src/main/java/org/apache/calcite/sql/SqlDialectFactoryImpl.java
b/core/src/main/java/org/apache/calcite/sql/SqlDialectFactoryImpl.java
index db5b505..f26f940 100644
--- a/core/src/main/java/org/apache/calcite/sql/SqlDialectFactoryImpl.java
+++ b/core/src/main/java/org/apache/calcite/sql/SqlDialectFactoryImpl.java
@@ -42,6 +42,7 @@ import org.apache.calcite.sql.dialect.ParaccelSqlDialect;
import org.apache.calcite.sql.dialect.PhoenixSqlDialect;
import org.apache.calcite.sql.dialect.PostgresqlSqlDialect;
import org.apache.calcite.sql.dialect.RedshiftSqlDialect;
+import org.apache.calcite.sql.dialect.SparkSqlDialect;
import org.apache.calcite.sql.dialect.SybaseSqlDialect;
import org.apache.calcite.sql.dialect.TeradataSqlDialect;
import org.apache.calcite.sql.dialect.VerticaSqlDialect;
@@ -116,6 +117,8 @@ public class SqlDialectFactoryImpl implements
SqlDialectFactory {
return new MysqlSqlDialect(c);
case "REDSHIFT":
return new RedshiftSqlDialect(c);
+ case "SPARK":
+ return new SparkSqlDialect(c);
}
// Now the fuzzy matches.
if (databaseProductName.startsWith("DB2")) {
@@ -144,6 +147,8 @@ public class SqlDialectFactoryImpl implements
SqlDialectFactory {
return new H2SqlDialect(c);
} else if (upperProductName.contains("VERTICA")) {
return new VerticaSqlDialect(c);
+ } else if (upperProductName.contains("SPARK")) {
+ return new SparkSqlDialect(c);
} else {
return new AnsiSqlDialect(c);
}
@@ -232,6 +237,8 @@ public class SqlDialectFactoryImpl implements
SqlDialectFactory {
return TeradataSqlDialect.DEFAULT;
case VERTICA:
return VerticaSqlDialect.DEFAULT;
+ case SPARK:
+ return SparkSqlDialect.DEFAULT;
case SQLSTREAM:
case UNKNOWN:
default:
diff --git
a/core/src/main/java/org/apache/calcite/sql/dialect/SparkSqlDialect.java
b/core/src/main/java/org/apache/calcite/sql/dialect/SparkSqlDialect.java
new file mode 100644
index 0000000..f37eb5a
--- /dev/null
+++ b/core/src/main/java/org/apache/calcite/sql/dialect/SparkSqlDialect.java
@@ -0,0 +1,60 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.calcite.sql.dialect;
+
+import org.apache.calcite.config.NullCollation;
+import org.apache.calcite.sql.JoinType;
+import org.apache.calcite.sql.SqlDialect;
+import org.apache.calcite.sql.SqlNode;
+import org.apache.calcite.sql.SqlWriter;
+
+/**
+ * A <code>SqlDialect</code> implementation for the APACHE SPARK database.
+ */
+public class SparkSqlDialect extends SqlDialect {
+ public static final SqlDialect DEFAULT =
+ new SparkSqlDialect(EMPTY_CONTEXT
+ .withDatabaseProduct(DatabaseProduct.SPARK)
+ .withNullCollation(NullCollation.LOW));
+
+ /**
+ * Creates a SparkSqlDialect.
+ */
+ public SparkSqlDialect(SqlDialect.Context context) {
+ super(context);
+ }
+
+ @Override protected boolean allowsAs() {
+ return false;
+ }
+
+ @Override public boolean supportsCharSet() {
+ return false;
+ }
+
+ @Override public JoinType emulateJoinTypeForCrossJoin() {
+ return JoinType.CROSS;
+ }
+
+
+ @Override public void unparseOffsetFetch(SqlWriter writer, SqlNode offset,
+ SqlNode fetch) {
+ unparseFetchUsingLimit(writer, offset, fetch);
+ }
+}
+
+// End SparkSqlDialect.java
diff --git
a/core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java
b/core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java
index b5afdf5..0932f37 100644
---
a/core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java
+++
b/core/src/test/java/org/apache/calcite/rel/rel2sql/RelToSqlConverterTest.java
@@ -3046,6 +3046,14 @@ public class RelToSqlConverterTest {
sql(query).ok(expected);
}
+ @Test public void testCrossJoinEmulationForSpark() {
+ String query = "select * from \"employee\", \"department\"";
+ final String expected = "SELECT *\n"
+ + "FROM foodmart.employee\n"
+ + "CROSS JOIN foodmart.department";
+ sql(query).withSpark().ok(expected);
+ }
+
/** Fluid interface to run tests. */
static class Sql {
private final SchemaPlus schema;
@@ -3115,6 +3123,10 @@ public class RelToSqlConverterTest {
return dialect(SqlDialect.DatabaseProduct.BIG_QUERY.getDialect());
}
+ Sql withSpark() {
+ return dialect(DatabaseProduct.SPARK.getDialect());
+ }
+
Sql withPostgresqlModifiedTypeSystem() {
// Postgresql dialect with max length for varchar set to 256
final PostgresqlSqlDialect postgresqlSqlDialect =
