From 89b9c5a46422850ffd3900db9fa9651c515bd112 Mon Sep 17 00:00:00 2001
From: Lukas Eder <lukas.eder@datageekery.com>
Date: Mon, 25 Mar 2024 10:58:25 +0100
Subject: [PATCH] [jOOQ/jOOQ#16499] Prototype API and implement ARRAY_FILTER

---
 jOOQ/src/main/java/org/jooq/Lambda1.java      |  59 +++++
 .../main/java/org/jooq/impl/ArrayFilter.java  | 203 ++++++++++++++++++
 jOOQ/src/main/java/org/jooq/impl/DSL.java     |  70 ++++++
 .../main/java/org/jooq/impl/LambdaImpl1.java  | 109 ++++++++++
 jOOQ/src/main/java/org/jooq/impl/QOM.java     |  64 ++++++
 5 files changed, 505 insertions(+)
 create mode 100644 jOOQ/src/main/java/org/jooq/Lambda1.java
 create mode 100644 jOOQ/src/main/java/org/jooq/impl/ArrayFilter.java
 create mode 100644 jOOQ/src/main/java/org/jooq/impl/LambdaImpl1.java

diff --git a/jOOQ/src/main/java/org/jooq/Lambda1.java b/jOOQ/src/main/java/org/jooq/Lambda1.java
new file mode 100644
index 0000000000..3e11a2590e
--- /dev/null
+++ b/jOOQ/src/main/java/org/jooq/Lambda1.java
@@ -0,0 +1,59 @@
+/*
+ * Licensed 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
+ *
+ *  https://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.
+ *
+ * Other licenses:
+ * -----------------------------------------------------------------------------
+ * Commercial licenses for this work are available. These replace the above
+ * ASL 2.0 and offer limited warranties, support, maintenance, and commercial
+ * database integrations.
+ *
+ * For more information, please visit: https://www.jooq.org/legal/licensing
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ */
+package org.jooq;
+
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * A lambda expression of degree 1.
+ *
+ * @author Lukas Eder
+ */
+public interface Lambda1<T1, R> extends QueryPart {
+
+    /**
+     * The first argument of the lambda.
+     */
+    @NotNull Field<T1> $arg1();
+
+    /**
+     * The lambda result.
+     */
+    @NotNull Field<R> $result();
+
+}
diff --git a/jOOQ/src/main/java/org/jooq/impl/ArrayFilter.java b/jOOQ/src/main/java/org/jooq/impl/ArrayFilter.java
new file mode 100644
index 0000000000..467935e174
--- /dev/null
+++ b/jOOQ/src/main/java/org/jooq/impl/ArrayFilter.java
@@ -0,0 +1,203 @@
+/*
+ * Licensed 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
+ *
+ *  https://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.
+ *
+ * Other licenses:
+ * -----------------------------------------------------------------------------
+ * Commercial licenses for this work are available. These replace the above
+ * ASL 2.0 and offer limited warranties, support, maintenance, and commercial
+ * database integrations.
+ *
+ * For more information, please visit: https://www.jooq.org/legal/licensing
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ */
+package org.jooq.impl;
+
+import static org.jooq.impl.DSL.*;
+import static org.jooq.impl.Internal.*;
+import static org.jooq.impl.Keywords.*;
+import static org.jooq.impl.Names.*;
+import static org.jooq.impl.SQLDataType.*;
+import static org.jooq.impl.Tools.*;
+import static org.jooq.impl.Tools.BooleanDataKey.*;
+import static org.jooq.impl.Tools.ExtendedDataKey.*;
+import static org.jooq.impl.Tools.SimpleDataKey.*;
+import static org.jooq.SQLDialect.*;
+
+import org.jooq.*;
+import org.jooq.Function1;
+import org.jooq.Record;
+import org.jooq.conf.*;
+import org.jooq.impl.*;
+import org.jooq.impl.QOM.*;
+import org.jooq.tools.*;
+
+import java.util.*;
+import java.util.function.*;
+import java.util.stream.*;
+
+
+/**
+ * The <code>ARRAY FILTER</code> statement.
+ */
+@SuppressWarnings({ "rawtypes", "unchecked", "unused" })
+final class ArrayFilter<T>
+extends
+    AbstractField<T[]>
+implements
+    QOM.ArrayFilter<T>
+{
+
+    final Field<T[]>          array;
+    final Lambda1<T, Boolean> filter;
+
+    ArrayFilter(
+        Field<T[]> array,
+        Lambda1<T, Boolean> filter
+    ) {
+        super(
+            N_ARRAY_FILTER,
+            allNotNull((DataType) dataType(((DataType) OTHER).array(), array, false), array)
+        );
+
+        this.array = nullSafeNotNull(array, ((DataType) OTHER).array());
+        this.filter = filter;
+    }
+
+    // -------------------------------------------------------------------------
+    // XXX: QueryPart API
+    // -------------------------------------------------------------------------
+
+    @Override
+    final boolean parenthesised(Context<?> ctx) {
+        switch (ctx.family()) {
+
+
+            case H2:
+            case HSQLDB:
+            case POSTGRES:
+            case YUGABYTEDB:
+                return false;
+
+            case DUCKDB:
+                return true;
+
+            default:
+                return true;
+        }
+    }
+
+    @Override
+    public final void accept(Context<?> ctx) {
+        switch (ctx.family()) {
+
+
+
+
+
+
+
+
+            case H2:
+            case HSQLDB:
+            case POSTGRES:
+            case YUGABYTEDB:
+                ctx.visit(DSL.field(
+                    select(DSL.coalesce(arrayAgg(filter.$arg1()), when(array.isNotNull(), DSL.cast(array(), getDataType()))))
+                    .from(unnest(array).as(N_T, filter.$arg1().getUnqualifiedName()))
+                    .where(filter.$result())
+                ));
+                break;
+
+            case DUCKDB:
+                ctx.visit(function(N_ARRAY_FILTER, getDataType(), array, DSL.field("{0}", OTHER, filter)));
+                break;
+
+            default:
+                ctx.visit(function(N_ARRAY_FILTER, getDataType(), array, DSL.field("{0}", OTHER, filter)));
+                break;
+        }
+    }
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+    // -------------------------------------------------------------------------
+    // XXX: Query Object Model
+    // -------------------------------------------------------------------------
+
+    @Override
+    public final Field<T[]> $arg1() {
+        return array;
+    }
+
+    @Override
+    public final Lambda1<T, Boolean> $arg2() {
+        return filter;
+    }
+
+    @Override
+    public final QOM.ArrayFilter<T> $arg1(Field<T[]> newValue) {
+        return $constructor().apply(newValue, $arg2());
+    }
+
+    @Override
+    public final QOM.ArrayFilter<T> $arg2(Lambda1<T, Boolean> newValue) {
+        return $constructor().apply($arg1(), newValue);
+    }
+
+    @Override
+    public final Function2<? super Field<T[]>, ? super Lambda1<T, Boolean>, ? extends QOM.ArrayFilter<T>> $constructor() {
+        return (a1, a2) -> new ArrayFilter<>(a1, a2);
+    }
+
+    // -------------------------------------------------------------------------
+    // XXX: The Object API
+    // -------------------------------------------------------------------------
+
+    @Override
+    public boolean equals(Object that) {
+        if (that instanceof QOM.ArrayFilter<?> o) {
+            return
+                StringUtils.equals($array(), o.$array()) &&
+                StringUtils.equals($filter(), o.$filter())
+            ;
+        }
+        else
+            return super.equals(that);
+    }
+}
diff --git a/jOOQ/src/main/java/org/jooq/impl/DSL.java b/jOOQ/src/main/java/org/jooq/impl/DSL.java
index 3ace9a109b..002ba605d5 100644
--- a/jOOQ/src/main/java/org/jooq/impl/DSL.java
+++ b/jOOQ/src/main/java/org/jooq/impl/DSL.java
@@ -110,6 +110,7 @@ import static org.jooq.conf.ParamType.INLINED;
 import static org.jooq.impl.Names.N_COUNT;
 import static org.jooq.impl.Names.N_CUME_DIST;
 import static org.jooq.impl.Names.N_DENSE_RANK;
+import static org.jooq.impl.Names.N_E;
 import static org.jooq.impl.Names.N_IF;
 import static org.jooq.impl.Names.N_IIF;
 import static org.jooq.impl.Names.N_PERCENTILE_CONT;
@@ -223,6 +224,7 @@ import org.jooq.False;
 import org.jooq.Field;
 import org.jooq.FieldOrRow;
 // ...
+import org.jooq.Function1;
 import org.jooq.Geography;
 import org.jooq.Geometry;
 import org.jooq.GroupConcatOrderByStep;
@@ -269,6 +271,7 @@ import org.jooq.JSONTableColumnsFirstStep;
 import org.jooq.JSONValueOnStep;
 import org.jooq.Keyword;
 // ...
+import org.jooq.Lambda1;
 // ...
 // ...
 import org.jooq.Merge;
@@ -14029,6 +14032,29 @@ public class DSL {
 
 
 
+
+    // -------------------------------------------------------------------------
+    // XXX: Lambda constructors
+    // -------------------------------------------------------------------------
+
+    @Support({ CLICKHOUSE, DUCKDB, H2, HSQLDB, POSTGRES, TRINO, YUGABYTEDB })
+    @NotNull
+    static <T1, R> Lambda1<T1, R> lambda(T1[] field, org.jooq.Function1<? super Field<T1>, ? extends Field<R>> function) {
+        return lambda(Tools.field(field), function);
+    }
+
+    @Support({ CLICKHOUSE, DUCKDB, H2, HSQLDB, POSTGRES, TRINO, YUGABYTEDB })
+    @NotNull
+    static <T1, R> Lambda1<T1, R> lambda(Field<T1[]> field, org.jooq.Function1<? super Field<T1>, ? extends Field<R>> function) {
+        Field<T1> e = (Field<T1>) DSL.field(N_E, field.getDataType().getArrayBaseDataType());
+        return lambda(e, function.apply(e));
+    }
+
+    @Support({ CLICKHOUSE, DUCKDB, H2, HSQLDB, POSTGRES, TRINO, YUGABYTEDB })
+    @NotNull
+    public static <T1, R> Lambda1<T1, R> lambda(Field<T1> arg1, Field<R> result) {
+        return new org.jooq.impl.LambdaImpl1<>(arg1, result);
+    }
 
     // -------------------------------------------------------------------------
     // XXX: Routine parameter constructors
@@ -22394,6 +22420,50 @@ public class DSL {
         return new ArrayReplace<>(arg1, arg2, arg3);
     }
 
+    /**
+     * The <code>ARRAY_FILTER</code> function.
+     * <p>
+     * Filter elements out of an array.
+     */
+    @NotNull
+    @Support({ CLICKHOUSE, DUCKDB, H2, HSQLDB, POSTGRES, TRINO, YUGABYTEDB })
+    public static <T> Field<T[]> arrayFilter(T[] array, Function1<? super Field<T>, ? extends Field<Boolean>> filter) {
+        return new ArrayFilter<>(Tools.field(array), DSL.lambda(array, filter));
+    }
+
+    /**
+     * The <code>ARRAY_FILTER</code> function.
+     * <p>
+     * Filter elements out of an array.
+     */
+    @NotNull
+    @Support({ CLICKHOUSE, DUCKDB, H2, HSQLDB, POSTGRES, TRINO, YUGABYTEDB })
+    public static <T> Field<T[]> arrayFilter(T[] array, Lambda1<T, Boolean> filter) {
+        return new ArrayFilter<>(Tools.field(array), filter);
+    }
+
+    /**
+     * The <code>ARRAY_FILTER</code> function.
+     * <p>
+     * Filter elements out of an array.
+     */
+    @NotNull
+    @Support({ CLICKHOUSE, DUCKDB, H2, HSQLDB, POSTGRES, TRINO, YUGABYTEDB })
+    public static <T> Field<T[]> arrayFilter(Field<T[]> array, Function1<? super Field<T>, ? extends Field<Boolean>> filter) {
+        return new ArrayFilter<>(array, DSL.lambda(array, filter));
+    }
+
+    /**
+     * The <code>ARRAY_FILTER</code> function.
+     * <p>
+     * Filter elements out of an array.
+     */
+    @NotNull
+    @Support({ CLICKHOUSE, DUCKDB, H2, HSQLDB, POSTGRES, TRINO, YUGABYTEDB })
+    public static <T> Field<T[]> arrayFilter(Field<T[]> array, Lambda1<T, Boolean> filter) {
+        return new ArrayFilter<>(array, filter);
+    }
+
     // -------------------------------------------------------------------------
     // Utility functions
     // -------------------------------------------------------------------------
diff --git a/jOOQ/src/main/java/org/jooq/impl/LambdaImpl1.java b/jOOQ/src/main/java/org/jooq/impl/LambdaImpl1.java
new file mode 100644
index 0000000000..5c61bd1c50
--- /dev/null
+++ b/jOOQ/src/main/java/org/jooq/impl/LambdaImpl1.java
@@ -0,0 +1,109 @@
+/*
+ * Licensed 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
+ *
+ *  https://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.
+ *
+ * Other licenses:
+ * -----------------------------------------------------------------------------
+ * Commercial licenses for this work are available. These replace the above
+ * ASL 2.0 and offer limited warranties, support, maintenance, and commercial
+ * database integrations.
+ *
+ * For more information, please visit: https://www.jooq.org/legal/licensing
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ */
+package org.jooq.impl;
+
+import static org.jooq.impl.Names.N_E;
+
+import org.jooq.Context;
+import org.jooq.Field;
+import org.jooq.Function1;
+import org.jooq.Lambda1;
+import org.jooq.QueryPart;
+// ...
+// ...
+
+/**
+ * @author Lukas Eder
+ */
+final class LambdaImpl1<T1, R>
+extends
+    AbstractQueryPart
+implements
+    Lambda1<T1, R>
+{
+
+    final Field<T1> arg1;
+    final Field<R>  result;
+
+    LambdaImpl1(Field<T1> arg1, Field<R> result) {
+        this.arg1 = arg1;
+        this.result = result;
+    }
+
+    // -------------------------------------------------------------------------
+    // XXX: QueryPart API
+    // -------------------------------------------------------------------------
+
+    @Override
+    public final void accept(Context<?> ctx) {
+        ctx.visit(arg1).sql(" -> ").visit(result);
+    }
+
+    // -------------------------------------------------------------------------
+    // XXX: Query Object Model
+    // -------------------------------------------------------------------------
+
+    @Override
+    public final Field<T1> $arg1() {
+        return arg1;
+    }
+
+    @Override
+    public final Field<R> $result() {
+        return result;
+    }
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+    // -------------------------------------------------------------------------
+    // XXX: Object API
+    // -------------------------------------------------------------------------
+
+}
diff --git a/jOOQ/src/main/java/org/jooq/impl/QOM.java b/jOOQ/src/main/java/org/jooq/impl/QOM.java
index ecd623cfe9..0c8c949949 100644
--- a/jOOQ/src/main/java/org/jooq/impl/QOM.java
+++ b/jOOQ/src/main/java/org/jooq/impl/QOM.java
@@ -103,6 +103,7 @@ import org.jooq.JSON;
 import org.jooq.JSONB;
 import org.jooq.JSONEntry;
 import org.jooq.Keyword;
+import org.jooq.Lambda1;
 // ...
 import org.jooq.Name;
 import org.jooq.Operator;
@@ -228,6 +229,22 @@ public final class QOM {
     // XXX: Model
     // -------------------------------------------------------------------------
 
+//    public interface Lambda1<T1, R>
+//        extends
+//            org.jooq.QueryPart
+//    {
+//
+//        /**
+//         * The first argument of the lambda.
+//         */
+//        @NotNull Field<T1> $arg1();
+//
+//        /**
+//         * The lambda result.
+//         */
+//        @NotNull Field<R> $result();
+//    }
+
     // This class uses a lot of fully qualified types, because of some javac bug
     // In Java 1.8.0_302, which hasn't been analysed and reproduced yet in a more
     // minimal example. Without the qualification, the types cannot be found
@@ -11757,6 +11774,53 @@ public final class QOM {
         //    ArrayReplace
     {}
 
+    /**
+     * The <code>ARRAY FILTER</code> function.
+     * <p>
+     * Filter elements out of an array.
+     */
+    public static final <T> ArrayFilter<T> ArrayFilter() {
+        return new org.jooq.impl.ArrayFilter<>(
+            null,
+            null
+        );
+    }
+
+    /**
+     * The <code>ARRAY FILTER</code> function.
+     * <p>
+     * Filter elements out of an array.
+     */
+    public static final <T> ArrayFilter<T> ArrayFilter(
+        Field<T[]> array,
+        Lambda1<T, Boolean> filter
+    ) {
+        return new org.jooq.impl.ArrayFilter<>(
+            array,
+            filter
+        );
+    }
+
+    /**
+     * The <code>ARRAY FILTER</code> function.
+     * <p>
+     * Filter elements out of an array.
+     */
+    public /*sealed*/ interface ArrayFilter<T>
+        extends
+            UOperator2<Field<T[]>, Lambda1<T, Boolean>, ArrayFilter<T>>,
+            org.jooq.Field<T[]>
+        //permits
+        //    ArrayFilter
+    {
+        @NotNull default Field<T[]> $array() { return $arg1(); }
+        @CheckReturnValue
+        @NotNull default ArrayFilter<T> $array(Field<T[]> newArray) { return $arg1(newArray); }
+        @NotNull default Lambda1<T, Boolean> $filter() { return $arg2(); }
+        @CheckReturnValue
+        @NotNull default ArrayFilter<T> $filter(Lambda1<T, Boolean> newFilter) { return $arg2(newFilter); }
+    }
+
     /**
      * The <code>NVL</code> function.
      * <p>