diff --git a/core/src/main/java/org/apache/calcite/rel/type/RelDataTypeSystem.java b/core/src/main/java/org/apache/calcite/rel/type/RelDataTypeSystem.java
index 5becafc2b74b..c9d6186747be 100644
--- a/core/src/main/java/org/apache/calcite/rel/type/RelDataTypeSystem.java
+++ b/core/src/main/java/org/apache/calcite/rel/type/RelDataTypeSystem.java
@@ -96,53 +96,29 @@ public interface RelDataTypeSystem {
    *
    * @deprecated Replaced by {@link #getMaxScale}(DECIMAL).
    *
-   * <p>From Calcite release 1.38 onwards, instead of calling this method, you
-   * should call {@code getMaxScale(DECIMAL)}.
+   * <p>Instead of calling this method, you should call
+   * {@code getMaxScale(DECIMAL)}.
    *
-   * <p>In Calcite release 1.38, if you wish to change the maximum
-   * scale of {@link SqlTypeName#DECIMAL} values, you should do two things:
-   *
-   * <ul>
-   * <li>Override the {@link #getMaxScale(SqlTypeName)} method,
-   *     changing its behavior for {@code DECIMAL};
-   * <li>Make sure that the implementation of your
-   *     {@code #getMaxNumericScale} method calls
-   *     {@code getMaxScale(DECIMAL)}.
-   * </ul>
-   *
-   * <p>In Calcite release 1.39, Calcite will cease calling this method,
-   * and will remove the override of the method in
-   * {@link RelDataTypeSystemImpl}. You should remove all calls to
-   * and overrides of this method. */
-  @Deprecated // calcite will cease calling in 1.39, and removed before 2.0
+   * <p>If you wish to change the maximum scale of {@link SqlTypeName#DECIMAL}
+   * values, override the {@link #getMaxScale(SqlTypeName)} method,
+   * changing its behavior for {@code DECIMAL}. */
+  @Deprecated // to be removed before 2.0
   default int getMaxNumericScale() {
-    return 19;
+    return getMaxScale(SqlTypeName.DECIMAL);
   }
 
   /** Returns the maximum precision of a NUMERIC or DECIMAL type.
    * Default value is 19.
    *
-   * @deprecated Replaced by {@link #getMaxScale}(DECIMAL).
+   * @deprecated Replaced by {@link #getMaxPrecision}(DECIMAL).
    *
-   * <p>From Calcite release 1.38 onwards, instead of calling this method, you
-   * should call {@code getMaxPrecision(DECIMAL)}.
-   *
-   * <p>In Calcite release 1.38, if you wish to change the maximum
-   * precision of {@link SqlTypeName#DECIMAL} values, you should do two things:
-   *
-   * <ul>
-   * <li>Override the {@link #getMaxPrecision(SqlTypeName)} method,
-   *     changing its behavior for {@code DECIMAL};
-   * <li>Make sure that the implementation of your
-   *     {@code #getMaxNumericPrecision} method calls
-   *     {@code getMaxPrecision(DECIMAL)}.
-   * </ul>
+   * <p>Instead of calling this method, you should call
+   * {@code getMaxPrecision(DECIMAL)}.
    *
-   * <p>In Calcite release 1.39, Calcite will cease calling this method,
-   * and will remove the override of the method in
-   * {@link RelDataTypeSystemImpl}. You should remove all calls to
-   * and overrides of this method. */
-  @Deprecated // calcite will cease calling in 1.39, and removed before 2.0
+   * <p>If you wish to change the maximum precision of {@link SqlTypeName#DECIMAL}
+   * values, override the {@link #getMaxPrecision(SqlTypeName)} method,
+   * changing its behavior for {@code DECIMAL}. */
+  @Deprecated // to be removed before 2.0
   default int getMaxNumericPrecision() {
     return getMaxPrecision(SqlTypeName.DECIMAL);
   }
diff --git a/core/src/main/java/org/apache/calcite/rel/type/RelDataTypeSystemImpl.java b/core/src/main/java/org/apache/calcite/rel/type/RelDataTypeSystemImpl.java
index b5eceedccefd..50d66f5e5f9c 100644
--- a/core/src/main/java/org/apache/calcite/rel/type/RelDataTypeSystemImpl.java
+++ b/core/src/main/java/org/apache/calcite/rel/type/RelDataTypeSystemImpl.java
@@ -46,8 +46,7 @@ public abstract class RelDataTypeSystemImpl implements RelDataTypeSystem {
   @Override public int getMaxScale(SqlTypeName typeName) {
     switch (typeName) {
     case DECIMAL:
-      // from 1.39, this will be 'return 19;'
-      return getMaxNumericScale();
+      return 19;
     case INTERVAL_YEAR:
     case INTERVAL_YEAR_MONTH:
     case INTERVAL_MONTH:
@@ -107,8 +106,7 @@ public abstract class RelDataTypeSystemImpl implements RelDataTypeSystem {
     case VARBINARY:
       return RelDataType.PRECISION_NOT_SPECIFIED;
     case DECIMAL:
-      // from 1.39, this will be 'return getMaxPrecision(typeName);'
-      return getMaxNumericPrecision();
+      return getMaxPrecision(typeName);
     case INTERVAL_YEAR:
     case INTERVAL_YEAR_MONTH:
     case INTERVAL_MONTH:
@@ -187,8 +185,7 @@ public abstract class RelDataTypeSystemImpl implements RelDataTypeSystem {
   @Override public int getMaxPrecision(SqlTypeName typeName) {
     switch (typeName) {
     case DECIMAL:
-      // from 1.39, this will be 'return 19;'
-      return getMaxNumericPrecision();
+      return 19;
     case VARCHAR:
     case CHAR:
       return 65536;
@@ -262,13 +259,13 @@ public abstract class RelDataTypeSystemImpl implements RelDataTypeSystem {
   }
 
   @SuppressWarnings("deprecation")
-  @Override public int getMaxNumericScale() {
-    return 19;
+  @Override public final int getMaxNumericScale() {
+    return getMaxScale(SqlTypeName.DECIMAL);
   }
 
   @SuppressWarnings("deprecation")
-  @Override public int getMaxNumericPrecision() {
-    return 19;
+  @Override public final int getMaxNumericPrecision() {
+    return getMaxPrecision(SqlTypeName.DECIMAL);
   }
 
   @Override public RoundingMode roundingMode() {
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 884bb81261f8..f33e49bb51d8 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
@@ -69,10 +69,6 @@ public class ClickHouseSqlDialect extends SqlDialect {
             return super.getMaxScale(typeName);
           }
         }
-
-        @Override public int getMaxNumericScale() {
-          return getMaxScale(SqlTypeName.DECIMAL);
-        }
       };
 
   public static final SqlDialect.Context DEFAULT_CONTEXT = SqlDialect.EMPTY_CONTEXT
diff --git a/core/src/main/java/org/apache/calcite/sql/dialect/DuckDBSqlDialect.java b/core/src/main/java/org/apache/calcite/sql/dialect/DuckDBSqlDialect.java
index e7d3333ba3c0..75b4dcc65388 100644
--- a/core/src/main/java/org/apache/calcite/sql/dialect/DuckDBSqlDialect.java
+++ b/core/src/main/java/org/apache/calcite/sql/dialect/DuckDBSqlDialect.java
@@ -54,10 +54,6 @@ public class DuckDBSqlDialect extends SqlDialect {
             return super.getMaxScale(typeName);
           }
         }
-
-        @Override public int getMaxNumericScale() {
-          return getMaxScale(SqlTypeName.DECIMAL);
-        }
       };
 
   public static final SqlDialect.Context DEFAULT_CONTEXT = SqlDialect.EMPTY_CONTEXT
diff --git a/core/src/main/java/org/apache/calcite/sql/dialect/PhoenixSqlDialect.java b/core/src/main/java/org/apache/calcite/sql/dialect/PhoenixSqlDialect.java
index 85bc64a89e9d..c3cebb92ae42 100644
--- a/core/src/main/java/org/apache/calcite/sql/dialect/PhoenixSqlDialect.java
+++ b/core/src/main/java/org/apache/calcite/sql/dialect/PhoenixSqlDialect.java
@@ -55,10 +55,6 @@ public class PhoenixSqlDialect extends SqlDialect {
             return super.getMaxScale(typeName);
           }
         }
-
-        @Override public int getMaxNumericScale() {
-          return getMaxScale(SqlTypeName.DECIMAL);
-        }
       };
 
   public static final SqlDialect.Context DEFAULT_CONTEXT = SqlDialect.EMPTY_CONTEXT
diff --git a/core/src/main/java/org/apache/calcite/sql/dialect/PrestoSqlDialect.java b/core/src/main/java/org/apache/calcite/sql/dialect/PrestoSqlDialect.java
index cd1aa5f5ec33..1d8479aa5811 100644
--- a/core/src/main/java/org/apache/calcite/sql/dialect/PrestoSqlDialect.java
+++ b/core/src/main/java/org/apache/calcite/sql/dialect/PrestoSqlDialect.java
@@ -84,10 +84,6 @@ public class PrestoSqlDialect extends SqlDialect {
             return super.getMaxScale(typeName);
           }
         }
-
-        @Override public int getMaxNumericScale() {
-          return getMaxScale(SqlTypeName.DECIMAL);
-        }
       };
 
   public static final Context DEFAULT_CONTEXT = SqlDialect.EMPTY_CONTEXT
diff --git a/core/src/main/java/org/apache/calcite/sql/dialect/RedshiftSqlDialect.java b/core/src/main/java/org/apache/calcite/sql/dialect/RedshiftSqlDialect.java
index 0875826a253a..7caf2ab2be24 100644
--- a/core/src/main/java/org/apache/calcite/sql/dialect/RedshiftSqlDialect.java
+++ b/core/src/main/java/org/apache/calcite/sql/dialect/RedshiftSqlDialect.java
@@ -49,10 +49,6 @@ public class RedshiftSqlDialect extends SqlDialect {
           }
         }
 
-        @Override public int getMaxNumericPrecision() {
-          return getMaxPrecision(SqlTypeName.DECIMAL);
-        }
-
         @Override public int getMaxScale(SqlTypeName typeName) {
           switch (typeName) {
           case DECIMAL:
@@ -61,10 +57,6 @@ public class RedshiftSqlDialect extends SqlDialect {
             return super.getMaxScale(typeName);
           }
         }
-
-        @Override public int getMaxNumericScale() {
-          return getMaxScale(SqlTypeName.DECIMAL);
-        }
       };
 
   public static final SqlDialect.Context DEFAULT_CONTEXT = SqlDialect.EMPTY_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 43e855592422..75cc30d27367 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
@@ -11380,10 +11380,6 @@ Sql withPostgresqlModifiedDecimalTypeSystem() {
           new PostgresqlSqlDialect(PostgresqlSqlDialect.DEFAULT_CONTEXT
               .withDataTypeSystem(
                   new RelDataTypeSystemImpl() {
-                    @Override public int getMaxNumericScale() {
-                      return getMaxScale(SqlTypeName.DECIMAL);
-                    }
-
                     @Override public int getMaxScale(SqlTypeName typeName) {
                       switch (typeName) {
                       case DECIMAL:
@@ -11393,10 +11389,6 @@ Sql withPostgresqlModifiedDecimalTypeSystem() {
                       }
                     }
 
-                    @Override public int getMaxNumericPrecision() {
-                      return getMaxPrecision(SqlTypeName.DECIMAL);
-                    }
-
                     @Override public int getMaxPrecision(SqlTypeName typeName) {
                       switch (typeName) {
                       case DECIMAL:
diff --git a/core/src/test/java/org/apache/calcite/sql/type/RelDataTypeSystemTest.java b/core/src/test/java/org/apache/calcite/sql/type/RelDataTypeSystemTest.java
index f21779f2c10a..2a96292eade8 100644
--- a/core/src/test/java/org/apache/calcite/sql/type/RelDataTypeSystemTest.java
+++ b/core/src/test/java/org/apache/calcite/sql/type/RelDataTypeSystemTest.java
@@ -127,15 +127,15 @@ private static final class CustomTypeSystem extends RelDataTypeSystemImpl {
       return type1;
     }
 
-    @Override public int getMaxNumericPrecision() {
-      return 38;
-    }
-
     @Override public int getMaxPrecision(SqlTypeName typeName) {
-      if (typeName == SqlTypeName.TIMESTAMP) {
+      switch (typeName) {
+      case DECIMAL:
+        return 38;
+      case TIMESTAMP:
         return CUSTOM_MAX_TIMESTAMP_PRECISION;
+      default:
+        return super.getMaxPrecision(typeName);
       }
-      return super.getMaxPrecision(typeName);
     }
   }
 
@@ -209,10 +209,6 @@ static class Fixture extends SqlTypeFixture {
      * Custom type system class that overrides the default max precision and max scale.
      */
     final class CustomTypeSystem extends RelDataTypeSystemImpl {
-      @Override public int getMaxNumericPrecision() {
-        return getMaxPrecision(SqlTypeName.DECIMAL);
-      }
-
       @Override public int getMaxPrecision(SqlTypeName typeName) {
         switch (typeName) {
         case DECIMAL:
@@ -222,10 +218,6 @@ final class CustomTypeSystem extends RelDataTypeSystemImpl {
         }
       }
 
-      @Override public int getMaxNumericScale() {
-        return getMaxScale(SqlTypeName.DECIMAL);
-      }
-
       @Override public int getMaxScale(SqlTypeName typeName) {
         switch (typeName) {
         case DECIMAL:
diff --git a/core/src/test/java/org/apache/calcite/tools/FrameworksTest.java b/core/src/test/java/org/apache/calcite/tools/FrameworksTest.java
index ed93b27c3da9..b413cc8b0125 100644
--- a/core/src/test/java/org/apache/calcite/tools/FrameworksTest.java
+++ b/core/src/test/java/org/apache/calcite/tools/FrameworksTest.java
@@ -530,11 +530,6 @@ public static class HiveLikeTypeSystem extends RelDataTypeSystemImpl {
 
     private HiveLikeTypeSystem() {}
 
-    @Override public int getMaxNumericPrecision() {
-      assert super.getMaxNumericPrecision() == 19;
-      return getMaxPrecision(SqlTypeName.DECIMAL);
-    }
-
     @Override public int getMaxPrecision(SqlTypeName typeName) {
       switch (typeName) {
       case DECIMAL:
@@ -550,11 +545,6 @@ private HiveLikeTypeSystem() {}
   public static class HiveLikeTypeSystem2 extends RelDataTypeSystemImpl {
     public HiveLikeTypeSystem2() {}
 
-    @Override public int getMaxNumericPrecision() {
-      assert super.getMaxNumericPrecision() == 19;
-      return getMaxPrecision(SqlTypeName.DECIMAL);
-    }
-
     @Override public int getMaxPrecision(SqlTypeName typeName) {
       switch (typeName) {
       case DECIMAL: