From 2af798aae1985ce4d91e9169bc13a8789f863ba3 Mon Sep 17 00:00:00 2001
From: lukaseder <lukas.eder@gmail.com>
Date: Wed, 5 Dec 2018 13:08:20 +0100
Subject: [PATCH] [#8087] Add support for overloaded functions in H2

---
 .../main/java/org/jooq/meta/h2/H2Database.java | 18 +++++++++++++++++-
 .../org/jooq/meta/h2/H2RoutineDefinition.java  | 10 +++++++++-
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/jOOQ-meta/src/main/java/org/jooq/meta/h2/H2Database.java b/jOOQ-meta/src/main/java/org/jooq/meta/h2/H2Database.java
index 1f46ce6d06..371be570d6 100644
--- a/jOOQ-meta/src/main/java/org/jooq/meta/h2/H2Database.java
+++ b/jOOQ-meta/src/main/java/org/jooq/meta/h2/H2Database.java
@@ -38,7 +38,10 @@
 package org.jooq.meta.h2;
 
 import static org.jooq.impl.DSL.falseCondition;
+import static org.jooq.impl.DSL.field;
 import static org.jooq.impl.DSL.inline;
+import static org.jooq.impl.DSL.name;
+import static org.jooq.impl.DSL.one;
 import static org.jooq.impl.DSL.select;
 import static org.jooq.meta.h2.information_schema.tables.Columns.COLUMNS;
 import static org.jooq.meta.h2.information_schema.tables.Constraints.CONSTRAINTS;
@@ -431,6 +434,14 @@ public class H2Database extends AbstractDatabase {
     protected List<RoutineDefinition> getRoutines0() throws SQLException {
         List<RoutineDefinition> result = new ArrayList<RoutineDefinition>();
 
+        Field<Boolean> overloaded = field(select(field(DSL.exists(
+            select(one())
+            .from(FUNCTION_ALIASES.as("a"))
+            .where(field(name("a", FunctionAliases.ALIAS_SCHEMA.getName())).eq(FunctionAliases.ALIAS_SCHEMA))
+            .and(field(name("a", FunctionAliases.ALIAS_NAME.getName())).eq(FunctionAliases.ALIAS_NAME))
+            .and(field(name("a", FunctionAliases.COLUMN_COUNT.getName())).ne(FunctionAliases.COLUMN_COUNT))
+        )))).as("overloaded");
+
         for (Record record : create()
                 .select(
                     FunctionAliases.ALIAS_SCHEMA,
@@ -438,6 +449,8 @@ public class H2Database extends AbstractDatabase {
                     FunctionAliases.REMARKS,
                     FunctionAliases.DATA_TYPE,
                     FunctionAliases.RETURNS_RESULT,
+                    FunctionAliases.COLUMN_COUNT,
+                    overloaded,
                     TypeInfo.TYPE_NAME,
                     TypeInfo.PRECISION,
                     TypeInfo.MAXIMUM_SCALE)
@@ -459,8 +472,11 @@ public class H2Database extends AbstractDatabase {
                 String typeName = record.get(TypeInfo.TYPE_NAME);
                 Integer precision = record.get(TypeInfo.PRECISION);
                 Short scale = record.get(TypeInfo.MAXIMUM_SCALE);
+                String overload = record.get(overloaded)
+                    ? record.get(FunctionAliases.COLUMN_COUNT, String.class)
+                    : null;
 
-                result.add(new H2RoutineDefinition(schema, name, comment, typeName, precision, scale));
+                result.add(new H2RoutineDefinition(schema, name, comment, typeName, precision, scale, overload));
             }
         }
 
diff --git a/jOOQ-meta/src/main/java/org/jooq/meta/h2/H2RoutineDefinition.java b/jOOQ-meta/src/main/java/org/jooq/meta/h2/H2RoutineDefinition.java
index 591ee8ad32..1737b1dc9c 100644
--- a/jOOQ-meta/src/main/java/org/jooq/meta/h2/H2RoutineDefinition.java
+++ b/jOOQ-meta/src/main/java/org/jooq/meta/h2/H2RoutineDefinition.java
@@ -38,6 +38,7 @@
 package org.jooq.meta.h2;
 
 
+import static org.jooq.impl.DSL.noCondition;
 import static org.jooq.meta.h2.information_schema.tables.FunctionColumns.FUNCTION_COLUMNS;
 
 import java.sql.SQLException;
@@ -63,7 +64,11 @@ import org.jooq.util.h2.H2DataType;
 public class H2RoutineDefinition extends AbstractRoutineDefinition {
 
     public H2RoutineDefinition(SchemaDefinition schema, String name, String comment, String typeName, Number precision, Number scale) {
-        super(schema, null, name, comment, null);
+        this(schema, name, comment, typeName, precision, scale, null);
+    }
+
+    public H2RoutineDefinition(SchemaDefinition schema, String name, String comment, String typeName, Number precision, Number scale, String overload) {
+        super(schema, null, name, comment, overload);
 
         if (!StringUtils.isBlank(typeName)) {
             DataTypeDefinition type = new DefaultDataTypeDefinition(
@@ -99,6 +104,9 @@ public class H2RoutineDefinition extends AbstractRoutineDefinition {
                 // [#4193] recent versions of H2 produce a row for the function
                 // return value at position 0
                 .and(FunctionColumns.POS.gt(0))
+                .and(getOverload() == null
+                    ? noCondition()
+                    : FunctionColumns.COLUMN_COUNT.eq(FunctionColumns.COLUMN_COUNT.getDataType().convert(getOverload())))
                 .orderBy(FunctionColumns.POS.asc()).fetch()) {
 
             String paramName = record.get(FunctionColumns.COLUMN_NAME);