From 8fce2683512bed955a7469e23d804a5dbb4038d6 Mon Sep 17 00:00:00 2001
From: Dominik Zalewski <dominik.zalewski@starburstdata.com>
Date: Mon, 28 Aug 2023 16:39:25 +0200
Subject: [PATCH] Add configuration property for max characters on alias column

---
 .../main/java/io/trino/plugin/jdbc/JdbcMetadataConfig.java | 7 +++++++
 .../trino/plugin/jdbc/JdbcMetadataSessionProperties.java   | 6 ++++++
 2 files changed, 13 insertions(+)

diff --git a/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/JdbcMetadataConfig.java b/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/JdbcMetadataConfig.java
index 039195481a86..e03b916678bb 100644
--- a/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/JdbcMetadataConfig.java
+++ b/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/JdbcMetadataConfig.java
@@ -41,6 +41,8 @@ public class JdbcMetadataConfig
     // between performance and pushdown capabilities
     private int domainCompactionThreshold = 32;
 
+    private int columnAliasMaxChars = 30;
+
     public boolean isComplexExpressionPushdownEnabled()
     {
         return complexExpressionPushdownEnabled;
@@ -100,6 +102,11 @@ public int getDomainCompactionThreshold()
         return domainCompactionThreshold;
     }
 
+    public int getColumnAliasMaxChars()
+    {
+        return this.columnAliasMaxChars;
+    }
+
     @Config("domain-compaction-threshold")
     @ConfigDescription("Maximum ranges to allow in a tuple domain without compacting it")
     public JdbcMetadataConfig setDomainCompactionThreshold(int domainCompactionThreshold)
diff --git a/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/JdbcMetadataSessionProperties.java b/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/JdbcMetadataSessionProperties.java
index d4ae2a0b5b12..ef41c6ba0ad2 100644
--- a/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/JdbcMetadataSessionProperties.java
+++ b/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/JdbcMetadataSessionProperties.java
@@ -36,6 +36,7 @@ public class JdbcMetadataSessionProperties
     public static final String AGGREGATION_PUSHDOWN_ENABLED = "aggregation_pushdown_enabled";
     public static final String TOPN_PUSHDOWN_ENABLED = "topn_pushdown_enabled";
     public static final String DOMAIN_COMPACTION_THRESHOLD = "domain_compaction_threshold";
+    public static final String COLUMN_ALIAS_MAX_CHARS = "column_alias_max_chars";
 
     private final List<PropertyMetadata<?>> properties;
 
@@ -70,6 +71,11 @@ public JdbcMetadataSessionProperties(JdbcMetadataConfig jdbcMetadataConfig, @Max
                         "Enable TopN pushdown",
                         jdbcMetadataConfig.isTopNPushdownEnabled(),
                         false))
+                .add(integerProperty(
+                        COLUMN_ALIAS_MAX_CHARS,
+                        "Maximum number of characters allowed in a column alias",
+                        jdbcMetadataConfig.getColumnAliasMaxChars(),
+                        false))
                 .build();
     }