From 5c0e37bbe19b382f722ed7aafd4a5dcc21b8be4a Mon Sep 17 00:00:00 2001
From: Jeremy Evans <code@jeremyevans.net>
Date: Thu, 22 Aug 2024 11:49:19 -0700
Subject: [PATCH] Support creating VIRTUAL tables on SQLite via the
 create_table :using option

---
 CHANGELOG                             |  2 ++
 lib/sequel/adapters/shared/sqlite.rb  |  4 +++-
 lib/sequel/database/schema_methods.rb |  2 ++
 spec/adapters/sqlite_spec.rb          | 13 +++++++++++++
 4 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG b/CHANGELOG
index 4e3c75e1b..7b536bde8 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,7 @@
 === master
 
+* Support creating VIRTUAL tables on SQLite via the create_table :using option (jeremyevans)
+
 * Support json_{exists,value,query} on PostgreSQL 17+ in the pg_json_ops extension (jeremyevans)
 
 * Remove documentation from the gem to reduce gem size by 25% (jeremyevans)
diff --git a/lib/sequel/adapters/shared/sqlite.rb b/lib/sequel/adapters/shared/sqlite.rb
index 6cfba71e1..61931099d 100644
--- a/lib/sequel/adapters/shared/sqlite.rb
+++ b/lib/sequel/adapters/shared/sqlite.rb
@@ -349,7 +349,7 @@ def connection_pragmas
         ps
       end
 
-      # Support creating STRICT AND/OR WITHOUT ROWID tables via :strict and :without_rowid options
+      # Support creating STRICT AND/OR WITHOUT ROWID tables via :strict and :without_rowid options, and VIRTUAL tables with :using option.
       def create_table_sql(name, generator, options)
         if options[:strict] && options[:without_rowid]
           "#{super} STRICT, WITHOUT ROWID"
@@ -357,6 +357,8 @@ def create_table_sql(name, generator, options)
           "#{super} STRICT"
         elsif options[:without_rowid]
           "#{super} WITHOUT ROWID"
+        elsif options[:using]
+          "CREATE VIRTUAL TABLE#{' IF NOT EXISTS' if options[:if_not_exists]} #{create_table_table_name_sql(name, options)} USING #{options[:using]}"
         else
           super
         end
diff --git a/lib/sequel/database/schema_methods.rb b/lib/sequel/database/schema_methods.rb
index c7cdd0c9f..0af43cb41 100644
--- a/lib/sequel/database/schema_methods.rb
+++ b/lib/sequel/database/schema_methods.rb
@@ -191,6 +191,8 @@ def create_join_table?(hash, options=OPTS)
     #            The +any+ type is treated like a SQLite column in a non-strict table,
     #            allowing any type of data to be stored. This option is supported on
     #            SQLite 3.37.0+.
+    # :using :: Create a VIRTUAL table with the given USING clause. The value should be
+    #           a string, as it is used directly in the SQL query.
     # :without_rowid :: Create a WITHOUT ROWID table. Every row in SQLite has a special
     #                   'rowid' column, that uniquely identifies that row within the table.
     #                   If this option is used, the 'rowid' column is omitted, which can
diff --git a/spec/adapters/sqlite_spec.rb b/spec/adapters/sqlite_spec.rb
index c4ef55479..1258121db 100644
--- a/spec/adapters/sqlite_spec.rb
+++ b/spec/adapters/sqlite_spec.rb
@@ -29,6 +29,19 @@
     @db.sqlite_version.must_be_kind_of(Integer)
   end
   
+  it "should support creating virtual tables via the create_table :using option" do
+    if @db['PRAGMA compile_options'].map(:compile_options).include?('ENABLE_FTS5')
+      @db.create_table(:fk, using: 'fts5(c)')
+      @db[:fk].insert(:c=>'foo bar')
+      @db[:fk].where(fk: 'foo').get(:c).must_equal 'foo bar'
+      @db[:fk].where(fk: 'bar').get(:c).must_equal 'foo bar'
+      @db[:fk].where(fk: 'baz').must_be_empty
+
+      @db.create_table(:fk, using: 'fts5(c)', if_not_exists: true)
+      @db[:fk].where(fk: 'foo').get(:c).must_equal 'foo bar'
+    end
+  end
+  
   it "should support dropping noncomposite unique constraint" do
     @db.create_table(:fk) do
       primary_key :id