diff --git a/src/hnsw.c b/src/hnsw.c
index a7210ea99..b46e5634c 100644
--- a/src/hnsw.c
+++ b/src/hnsw.c
@@ -455,6 +455,23 @@ HnswColumnType GetIndexColumnType(Relation index)
     return GetColumnTypeFromOid(attr->atttypid);
 }
 
+/*
+ * Returns length of vector from datum
+ */
+int DatumGetLength(Datum datum, HnswColumnType type)
+{
+    if(type == VECTOR) {
+        Vector *vector = DatumGetVector(datum);
+        return vector->dim;
+    } else if(type == REAL_ARRAY || type == INT_ARRAY) {
+        ArrayType *array = DatumGetArrayTypePCopy(datum);
+        return ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
+    } else {
+        elog(ERROR, "Unsupported type");
+    }
+    return -1;
+}
+
 /*
  * Given vector data and vector type, read it as either a float4 or int32 array and return as void*
  */
diff --git a/src/hnsw.h b/src/hnsw.h
index d1db4edc8..36b3e5172 100644
--- a/src/hnsw.h
+++ b/src/hnsw.h
@@ -38,6 +38,7 @@ PGDLLEXPORT Datum lantern_reindex_external_index(PG_FUNCTION_ARGS);
 
 HnswColumnType GetColumnTypeFromOid(Oid oid);
 HnswColumnType GetIndexColumnType(Relation index);
+int            DatumGetLength(Datum datum, HnswColumnType type);
 void*          DatumGetSizedArray(Datum datum, HnswColumnType type, int dimensions);
 
 #define LDB_UNUSED(x) (void)(x)
diff --git a/src/hnsw/build.c b/src/hnsw/build.c
index ebc0a8c99..0c7e3db4a 100644
--- a/src/hnsw/build.c
+++ b/src/hnsw/build.c
@@ -242,7 +242,7 @@ static int GetArrayLengthFromHeap(Relation heap, int indexCol, IndexInfo *indexI
     tuple = heap_getnext(scan, ForwardScanDirection);
     if(tuple == NULL) {
         heap_endscan(scan);
-        return n_items;
+        return 0;
     }
 
     if(indexInfo->ii_Expressions != NULL) {
@@ -361,8 +361,13 @@ static void InitBuildState(HnswBuildState *buildstate, Relation heap, Relation i
     if(heap != NULL && buildstate->dimensions < 1) {
         buildstate->dimensions = InferDimension(heap, indexInfo);
     }
-    /* Require column to have dimensions to be indexed */
-    if(buildstate->dimensions < 1) elog(ERROR, "column does not have dimensions, please specify one");
+
+    // At this point, (buildstate->dimensions == 0) if this is building an index with no dim specified on an empty table
+    // The zero is a sentinel value that we check upon the first insertion of a row
+    // Note that (buildstate->dimensions == -1) if something went wrong
+    if(buildstate->dimensions < 0) {
+        elog(ERROR, "could not infer a dimension when no dimension was specified");
+    }
 
     // not supported because of 8K page limit in postgres WAL pages
     // can pass this limit once quantization is supported
diff --git a/src/hnsw/insert.c b/src/hnsw/insert.c
index 6e5e090cd..bfd23a4c8 100644
--- a/src/hnsw/insert.c
+++ b/src/hnsw/insert.c
@@ -70,6 +70,7 @@ bool ldb_aminsert(Relation         index,
     GenericXLogState      *state;
     uint32                 new_tuple_id;
     HnswIndexTuple        *new_tuple;
+    HnswColumnType         column_type;
     usearch_init_options_t opts = {0};
     LDB_UNUSED(heap);
     LDB_UNUSED(indexInfo);
@@ -110,8 +111,23 @@ bool ldb_aminsert(Relation         index,
     hdr = (HnswIndexHeaderPage *)PageGetContents(hdr_page);
     assert(hdr->magicNumber == LDB_WAL_MAGIC_NUMBER);
 
-    opts.dimensions = hdr->vector_dim;
-    CheckHnswIndexDimensions(index, values[ 0 ], opts.dimensions);
+    datum = PointerGetDatum(PG_DETOAST_DATUM(values[ 0 ]));
+    column_type = GetIndexColumnType(index);
+
+    // Check if we created an index on an empty-table with no dimension specified
+    if(hdr->vector_dim == 0) {
+        opts.dimensions = DatumGetLength(datum, column_type);
+        if(opts.dimensions < 1)
+            elog(ERROR,
+                 "Failed to infer dimension of inserted vector upon first insert on an empty table with no index "
+                 "dimension specified.");
+        // update the index header (we mark hdr_buf dirty later)
+        hdr->vector_dim = opts.dimensions;
+    } else {
+        opts.dimensions = hdr->vector_dim;
+        CheckHnswIndexDimensions(index, values[ 0 ], opts.dimensions);
+    }
+
     PopulateUsearchOpts(index, &opts);
     opts.retriever_ctx = ldb_wal_retriever_area_init(index, hdr);
     opts.retriever = ldb_wal_index_node_retriever;
@@ -132,14 +148,13 @@ bool ldb_aminsert(Relation         index,
 
     insertstate->uidx = uidx;
     insertstate->retriever_ctx = opts.retriever_ctx;
-    insertstate->columnType = GetIndexColumnType(index);
+    insertstate->columnType = column_type;
 
     hdr_page = NULL;
 
     meta = usearch_metadata(uidx, &error);
     assert(!error);
 
-    datum = PointerGetDatum(PG_DETOAST_DATUM(values[ 0 ]));
     void *vector = DatumGetSizedArray(datum, insertstate->columnType, opts.dimensions);
 
 #if LANTERNDB_COPYNODES
diff --git a/test/expected/hnsw_create.out b/test/expected/hnsw_create.out
index 2d866705e..90e9a9206 100644
--- a/test/expected/hnsw_create.out
+++ b/test/expected/hnsw_create.out
@@ -92,18 +92,21 @@ CREATE TABLE small_world4 (
     id varchar(3),
     vector real[]
 );
--- If the first row is NULL we do not infer a dimension
+-- If the first inserted row is NULL: we can create an index but we can't infer the dimension from the first inserted row (since it is null)
 \set ON_ERROR_STOP off
-CREATE INDEX ON small_world4 USING hnsw (vector) WITH (M=14, ef=22, ef_construction=2);
-ERROR:  column does not have dimensions, please specify one
+CREATE INDEX first_row_null_idx ON small_world4 USING hnsw (vector) WITH (M=14, ef=22, ef_construction=2);
+INFO:  done init usearch index
+INFO:  inserted 0 elements
+INFO:  done saving 0 vectors
 begin;
 INSERT INTO small_world4 (id, vector) VALUES
 ('000', NULL),
 ('001', '{1,0,0,1}');
 CREATE INDEX ON small_world4 USING hnsw (vector) WITH (M=14, ef=22, ef_construction=2);
-ERROR:  column does not have dimensions, please specify one
+ERROR:  could not infer a dimension when no dimension was specified
 rollback;
 \set ON_ERROR_STOP on
+DROP INDEX first_row_null_idx;
 INSERT INTO small_world4 (id, vector) VALUES
 ('000', '{1,0,0,0}'),
 ('001', '{1,0,0,1}'),
@@ -151,3 +154,31 @@ CREATE INDEX ON small_world4 USING hnsw (vector) WITH (M=14, ef=22, ef_construct
 INFO:  done init usearch index
 ERROR:  Wrong number of dimensions: 3 instead of 4 expected
 \set ON_ERROR_STOP on
+-- Test index creation on empty table and no dimension specified
+CREATE TABLE small_world5 (
+    id SERIAL PRIMARY KEY,
+    v REAL[]
+);
+-- We can still create an index despite having an empty table and not specifying a dimension during index creation
+CREATE INDEX small_world5_hnsw_idx ON small_world5 USING hnsw (v dist_l2sq_ops);
+INFO:  done init usearch index
+INFO:  inserted 0 elements
+INFO:  done saving 0 vectors
+begin;
+-- Inserting a NULL vector should only insert it into the table and not into our index
+-- So, our index is still empty after and is yet to pick up a dimension
+INSERT INTO small_world5 (id, v) VALUES ('200', NULL);
+-- Our index then infers the dimension from the first inserted non-NULL row
+INSERT INTO small_world5 (id, v) VALUES
+('000', '{1,0,0,0,1}'),
+('001', '{1,0,0,1,2}'),
+('010', '{1,0,1,0,3}');
+rollback;
+-- Test that upon infering the dimension from the first inserted row, we do not allow subsequent rows with different dimensions 
+\set ON_ERROR_STOP off
+INSERT INTO small_world5 (id, v) VALUES
+('100', '{2,0,0,0,1}'),
+('101', '{2,0,0}'),
+('110', '{2,0,1,0}');
+ERROR:  Wrong number of dimensions: 3 instead of 5 expected
+\set ON_ERROR_STOP on
diff --git a/test/sql/hnsw_create.sql b/test/sql/hnsw_create.sql
index 776ddb2d0..a212ca8dc 100644
--- a/test/sql/hnsw_create.sql
+++ b/test/sql/hnsw_create.sql
@@ -36,9 +36,9 @@ CREATE TABLE small_world4 (
     id varchar(3),
     vector real[]
 );
--- If the first row is NULL we do not infer a dimension
+-- If the first inserted row is NULL: we can create an index but we can't infer the dimension from the first inserted row (since it is null)
 \set ON_ERROR_STOP off
-CREATE INDEX ON small_world4 USING hnsw (vector) WITH (M=14, ef=22, ef_construction=2);
+CREATE INDEX first_row_null_idx ON small_world4 USING hnsw (vector) WITH (M=14, ef=22, ef_construction=2);
 begin;
 INSERT INTO small_world4 (id, vector) VALUES
 ('000', NULL),
@@ -46,6 +46,7 @@ INSERT INTO small_world4 (id, vector) VALUES
 CREATE INDEX ON small_world4 USING hnsw (vector) WITH (M=14, ef=22, ef_construction=2);
 rollback;
 \set ON_ERROR_STOP on
+DROP INDEX first_row_null_idx;
 
 INSERT INTO small_world4 (id, vector) VALUES
 ('000', '{1,0,0,0}'),
@@ -78,3 +79,34 @@ UPDATE small_world4 SET vector = '{0,0,0}' WHERE id = '001';
 \set ON_ERROR_STOP off
 CREATE INDEX ON small_world4 USING hnsw (vector) WITH (M=14, ef=22, ef_construction=2);
 \set ON_ERROR_STOP on
+
+-- Test index creation on empty table and no dimension specified
+CREATE TABLE small_world5 (
+    id SERIAL PRIMARY KEY,
+    v REAL[]
+);
+
+-- We can still create an index despite having an empty table and not specifying a dimension during index creation
+CREATE INDEX small_world5_hnsw_idx ON small_world5 USING hnsw (v dist_l2sq_ops);
+
+begin;
+-- Inserting a NULL vector should only insert it into the table and not into our index
+-- So, our index is still empty after and is yet to pick up a dimension
+INSERT INTO small_world5 (id, v) VALUES ('200', NULL);
+
+-- Our index then infers the dimension from the first inserted non-NULL row
+INSERT INTO small_world5 (id, v) VALUES
+('000', '{1,0,0,0,1}'),
+('001', '{1,0,0,1,2}'),
+('010', '{1,0,1,0,3}');
+rollback;
+
+-- Test that upon infering the dimension from the first inserted row, we do not allow subsequent rows with different dimensions 
+\set ON_ERROR_STOP off
+INSERT INTO small_world5 (id, v) VALUES
+('100', '{2,0,0,0,1}'),
+('101', '{2,0,0}'),
+('110', '{2,0,1,0}');
+\set ON_ERROR_STOP on
+
+