Allow checking for existance of key - ignoring value

Author: jensj

ase/db/core.py

@@ -176,9 +176,6 @@ def new_generator(*args, **kwargs):
 
 class Database:
     """Base class for all databases."""
-
-    version = 2
-    
     def __init__(self, filename=None, create_indices=True,
                  use_lock_file=False):
         self.filename = filename

ase/db/jsondb.py

@@ -177,7 +177,9 @@ def _select(self, keywords, cmps, explain=False, verbosity=0, limit=None):
                 return
             dct = bigdct[id]
             for keyword in keywords:
-                if 'keywords' not in dct or keyword not in dct['keywords']:
+                if not (('keywords' in dct and keyword in dct['keywords']) or
+                        ('key_value_pairs' in dct and
+                         keyword in dct['key_value_pairs'])):
                     break
             else:
                 for key, op, val in cmps:

ase/db/sqlite.py

@@ -86,20 +86,21 @@ def _initialize(self, con):
 
         cur = con.execute(
             'select count(*) from sqlite_master where name="systems"')
+        self.version = 2
         if cur.fetchone()[0] == 0:
             for statement in init_statements:
                 con.execute(statement)
             if self.create_indices:
                 for statement in index_statements:
                     con.execute(statement)
             con.commit()
-            self.initialized = True
         else:
             cur = con.execute(
                 'select count(*) from sqlite_master where name="user_index"')
             if cur.fetchone()[0] == 1:
                 # Old version with "user" instead of "username" column
                 self.version = 1
+        self.initialized = True
 
     def _write(self, atoms, keywords, key_value_pairs, data):
         Database._write(self, atoms, keywords, key_value_pairs, data)
@@ -198,15 +199,17 @@ def _write(self, atoms, keywords, key_value_pairs, data):
                 assert isinstance(value, (str, unicode))
                 text_key_values.append([key, value, id])
 
-        if text_key_values:
-            cur.executemany('insert into text_key_values values (?, ?, ?)',
-                            text_key_values)
-        if number_key_values:
-            cur.executemany('insert into number_key_values values (?, ?, ?)',
-                            number_key_values)
-        if keywords:
-            cur.executemany('insert into keywords values (?, ?)',
-                            [(keyword, id) for keyword in keywords])
+        cur.executemany('insert into text_key_values values (?, ?, ?)',
+                        text_key_values)
+        cur.executemany('insert into number_key_values values (?, ?, ?)',
+                        number_key_values)
+        cur.executemany('insert into keywords values (?, ?)',
+                        [(keyword, id) for keyword in keywords])
+        
+        # Insert keys in keywords table also so that it is easy to query
+        # for the existance of keys:
+        cur.executemany('insert into keywords values (?, ?)',
+                        [(key, id) for key in key_value_pairs])
 
         con.commit()
         con.close()

ase/test/db.py

@@ -21,6 +21,9 @@
     assert con.get_atoms(H=1)[0].magmom == 1
     assert len(list(con.select('bla'))) == 0
     assert len(list(con.select(abc=42))) == 3
+    assert len(list(con.select('abc'))) == 3
+    assert len(list(con.select('abc,bla'))) == 0
+    assert len(list(con.select('abc,hydro'))) == 3
     assert len(list(con.select(foo='bar'))) == 0
     assert len(list(con.select(formula='H2'))) == 1
     assert len(list(con.select(formula='H2O'))) == 1

doc/ase/db/db.rst

@@ -101,7 +101,7 @@ Here are some example query strings:
     :widths: 25 75
 
     * - v3
-      - has 'v3' keyword
+      - has 'v3' key or keyword
     * - abc=H
       - has key 'abc' with value 'H'
     * - v3,abc=H