support float8 neighbors compression

Author: sivukhin

libsql-sqlite3/src/vectorIndex.c

@@ -404,6 +404,7 @@ static struct VectorParamName VECTOR_PARAM_NAMES[] = {
   { "metric",             VECTOR_METRIC_TYPE_PARAM_ID,        0, "cosine",    VECTOR_METRIC_TYPE_COS },
   { "metric",             VECTOR_METRIC_TYPE_PARAM_ID,        0, "l2",        VECTOR_METRIC_TYPE_L2 },
   { "compress_neighbors", VECTOR_COMPRESS_NEIGHBORS_PARAM_ID, 0, "float1bit", VECTOR_TYPE_FLOAT1BIT },
+  { "compress_neighbors", VECTOR_COMPRESS_NEIGHBORS_PARAM_ID, 0, "float8",    VECTOR_TYPE_FLOAT8 },
   { "compress_neighbors", VECTOR_COMPRESS_NEIGHBORS_PARAM_ID, 0, "float32",   VECTOR_TYPE_FLOAT32 },
   { "alpha",              VECTOR_PRUNING_ALPHA_PARAM_ID, 2, 0, 0 },
   { "search_l",           VECTOR_SEARCH_L_PARAM_ID,      1, 0, 0 },

libsql-sqlite3/test/libsql_vector_index.test

@@ -345,6 +345,33 @@ do_execsql_test vector-f64-compress-f32 {
   SELECT * FROM vector_top_k('t_f64_f32_idx', vector64('[10,-10,-20,20]'), 4);
 } {3 1 2}
 
+do_execsql_test vector-f32-compress-f8 {
+  CREATE TABLE t_f32_f8( v FLOAT32(4) );
+  CREATE INDEX t_f32_f8_idx ON t_f32_f8( libsql_vector_idx(v, 'compress_neighbors=float8') );
+  INSERT INTO t_f32_f8 VALUES ( vector('[1,-1,1,-1]') );
+  INSERT INTO t_f32_f8 VALUES ( vector('[-1,1,1,-1]') );
+  INSERT INTO t_f32_f8 VALUES ( vector('[1,-1,-1,1]') );
+  SELECT * FROM vector_top_k('t_f32_f8_idx', vector('[10,-10,-20,20]'), 4);
+} {3 1 2}
+
+do_execsql_test vector-f8 {
+  CREATE TABLE t_f8( v FLOAT8(4) );
+  CREATE INDEX t_f8_idx ON t_f8( libsql_vector_idx(v) );
+  INSERT INTO t_f8 VALUES ( vector8('[1,-1,1,-1]') );
+  INSERT INTO t_f8 VALUES ( vector8('[-1,1,1,-1]') );
+  INSERT INTO t_f8 VALUES ( vector8('[1,-1,-1,1]') );
+  SELECT * FROM vector_top_k('t_f8_idx', vector8('[10,-10,-20,20]'), 4);
+} {3 1 2}
+
+do_execsql_test vector-f8-compress-1bit {
+  CREATE TABLE t_f8_1bit( v FLOAT8(4) );
+  CREATE INDEX t_f8_1bit_idx ON t_f8_1bit( libsql_vector_idx(v, 'compress_neighbors=float1bit') );
+  INSERT INTO t_f8_1bit VALUES ( vector8('[1,-1,1,-1]') );
+  INSERT INTO t_f8_1bit VALUES ( vector8('[-1,1,1,-1]') );
+  INSERT INTO t_f8_1bit VALUES ( vector8('[1,-1,-1,1]') );
+  SELECT * FROM vector_top_k('t_f8_1bit_idx', vector8('[10,-10,-20,20]'), 4);
+} {3 1 2}
+
 proc error_messages {sql} {
   set ret ""
   catch {
@@ -355,6 +382,8 @@ proc error_messages {sql} {
   set ret [sqlite3_errmsg db]
 }
 
+reset_db
+
 do_test vector-errors {
   set ret [list]
   lappend ret [error_messages {CREATE INDEX t_no_idx ON t_no( libsql_vector_idx(v) )}]