(calcite) branch main updated: [CALCITE-6909] ClickHouse Dailect can not support accurate precision

[mbudiu]

This is an automated email from the ASF dual-hosted git repository.

mbudiu pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/calcite.git


The following commit(s) were added to refs/heads/main by this push:
     new bc60174737 [CALCITE-6909] ClickHouse Dailect can not support accurate 
precision
bc60174737 is described below

commit bc60174737c6c01e86615f793399860495cddbba
Author: Yu Xu <1206332...@qq.com>
AuthorDate: Mon Mar 24 12:45:17 2025 +0800

    [CALCITE-6909] ClickHouse Dailect can not support accurate precision
---
 .../calcite/sql/dialect/ClickHouseSqlDialect.java  | 30 +++++++++++++++++++++-
 .../calcite/rel/rel2sql/RelToSqlConverterTest.java | 22 +++++++++++++++-
 2 files changed, 50 insertions(+), 2 deletions(-)

diff --git 
a/core/src/main/java/org/apache/calcite/sql/dialect/ClickHouseSqlDialect.java 
b/core/src/main/java/org/apache/calcite/sql/dialect/ClickHouseSqlDialect.java
index fc85540872..6b64725971 100644
--- 
a/core/src/main/java/org/apache/calcite/sql/dialect/ClickHouseSqlDialect.java
+++ 
b/core/src/main/java/org/apache/calcite/sql/dialect/ClickHouseSqlDialect.java
@@ -19,6 +19,8 @@
 import org.apache.calcite.avatica.util.TimeUnitRange;
 import org.apache.calcite.config.NullCollation;
 import org.apache.calcite.rel.type.RelDataType;
+import org.apache.calcite.rel.type.RelDataTypeSystem;
+import org.apache.calcite.rel.type.RelDataTypeSystemImpl;
 import org.apache.calcite.sql.SqlAbstractDateTimeLiteral;
 import org.apache.calcite.sql.SqlBasicTypeNameSpec;
 import org.apache.calcite.sql.SqlCall;
@@ -48,10 +50,36 @@
  * A <code>SqlDialect</code> implementation for the ClickHouse database.
  */
 public class ClickHouseSqlDialect extends SqlDialect {
+  public static final RelDataTypeSystem TYPE_SYSTEM =
+      new RelDataTypeSystemImpl() {
+        @Override public int getMaxPrecision(SqlTypeName typeName) {
+          switch (typeName) {
+          case DECIMAL:
+            return 76;
+          default:
+            return super.getMaxPrecision(typeName);
+          }
+        }
+
+        @Override public int getMaxScale(SqlTypeName typeName) {
+          switch (typeName) {
+          case DECIMAL:
+            return 76;
+          default:
+            return super.getMaxScale(typeName);
+          }
+        }
+
+        @Override public int getMaxNumericScale() {
+          return getMaxScale(SqlTypeName.DECIMAL);
+        }
+      };
+
   public static final SqlDialect.Context DEFAULT_CONTEXT = 
SqlDialect.EMPTY_CONTEXT
       .withDatabaseProduct(SqlDialect.DatabaseProduct.CLICKHOUSE)
       .withIdentifierQuoteString("`")
-      .withNullCollation(NullCollation.LOW);
+      .withNullCollation(NullCollation.LOW)
+      .withDataTypeSystem(TYPE_SYSTEM);
 
   public static final SqlDialect DEFAULT = new 
ClickHouseSqlDialect(DEFAULT_CONTEXT);
 
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 f8fdf44e13..b815987236 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
@@ -1418,9 +1418,13 @@ private static String toSql(RelNode root, SqlDialect 
dialect,
         + "from \"product\" ";
     final String expectedRedshift = "SELECT CAST(\"product_id\" AS DECIMAL(38, 
2))\n"
         + "FROM \"foodmart\".\"product\"";
+    final String expectedClickHouse = "SELECT CAST(`product_id` AS DECIMAL(60, 
2))\n"
+        + "FROM `foodmart`.`product`";
     sql(query)
         .withRedshift()
-        .ok(expectedRedshift);
+        .ok(expectedRedshift)
+        .withClickHouse()
+        .ok(expectedClickHouse);
   }
 
   /**
@@ -5866,6 +5870,16 @@ private void checkLiteral2(String expression, String 
expected) {
         .ok(expected);
   }
 
+  /** Test for <a 
href="https://issues.apache.org/jira/browse/CALCITE-6909";>[CALCITE-6909]
+   *  ClickHouse dialect should limit the Precision and Scale of the Decimal 
type
+   *  to be within 76</a>. */
+  @Test void testClickHouseDecimalPrecision() {
+    final String sql = "SELECT CAST(1.23 AS DECIMAL(76, 20))";
+    final String expected = "SELECT 1.23000000000000000000";
+    sql(sql).withClickHouseModifiedDecimalTypeSystem()
+        .ok(expected);
+  }
+
   /** Test for <a 
href="https://issues.apache.org/jira/browse/CALCITE-5651";>[CALCITE-5651]
    * Inferred scale for decimal should not exceed maximum allowed scale</a>. */
   @Test void testNumericScale() {
@@ -9821,6 +9835,12 @@ Sql withPostgresqlModifiedDecimalTypeSystem() {
       return dialect(postgresqlSqlDialect);
     }
 
+    Sql withClickHouseModifiedDecimalTypeSystem() {
+      final ClickHouseSqlDialect clickHouseSqlDialect =
+          new ClickHouseSqlDialect(ClickHouseSqlDialect.DEFAULT_CONTEXT);
+      return dialect(clickHouseSqlDialect);
+    }
+
     Sql withOracleModifiedTypeSystem() {
       // Oracle dialect with max length for varchar set to 512
       final OracleSqlDialect oracleSqlDialect =