X-Git-Url: https://git.jsancho.org/?p=datasette-pytables.git;a=blobdiff_plain;f=datasette_pytables%2F__init__.py;h=93cc1f082fd6eef31e0250ef644080cf4474303c;hp=74c72b1173fd7af371c414255c181c1c6bdaa3be;hb=6e8ac54ac9cc83d82ae2482dcec518a1f09991fa;hpb=2ec11308121b4b9c0064ffdde3b583efb95228bc

diff --git a/datasette_pytables/__init__.py b/datasette_pytables/__init__.py
index 74c72b1..93cc1f0 100644
--- a/datasette_pytables/__init__.py
+++ b/datasette_pytables/__init__.py
@@ -71,7 +71,7 @@ class Connection:
         self.path = path
         self.h5file = tables.open_file(path)
 
-    def execute(self, sql, params=None, truncate=False, page_size=None):
+    def execute(self, sql, params=None, truncate=False, page_size=None, max_returned_rows=None):
         if params is None:
             params = {}
         rows = []
@@ -79,6 +79,10 @@ class Connection:
         description = []
 
         parsed_sql = _parse_sql(sql, params)
+
+        if parsed_sql['from'] == 'sqlite_master':
+            return self._execute_datasette_query(sql, params)
+
         table = self.h5file.get_node(parsed_sql['from'])
         table_rows = []
         fields = parsed_sql['select']
@@ -141,9 +145,11 @@ class Connection:
                 end = start + max_rows
 
         # Truncate if needed
-        if page_size and truncate:
-            if end - start > page_size:
-                end = start + page_size
+        if page_size and max_returned_rows and truncate:
+            if max_returned_rows == page_size:
+                max_returned_rows += 1
+            if end - start > max_returned_rows:
+                end = start + max_returned_rows
                 truncated = True
 
         # Execute query
@@ -211,12 +217,46 @@ class Connection:
         else:
             return rows
 
-class Row(OrderedDict):
-    def __getitem__(self, label):
-        if type(label) is int:
-            return super(OrderedDict, self).__getitem__(list(self.keys())[label])
+    def _execute_datasette_query(self, sql, params):
+        "Datasette special queries for getting tables info"
+        if sql == "SELECT count(*) from sqlite_master WHERE type = 'view' and name=:n":
+            row = Row()
+            row['count(*)'] = 0
+            return [row]
+        elif sql == 'select sql from sqlite_master where name = :n and type="table"':
+            try:
+                table = self.h5file.get_node(params['n'])
+                row = Row()
+                row['sql'] = 'CREATE TABLE {} ()'.format(params['n'])
+                return [row]
+            except:
+                return []
+        else:
+            raise Exception("SQLite queries cannot be executed with this connector")
+
+class Row(list):
+    def __init__(self, values=None):
+        self.labels = []
+        self.values = []
+        if values:
+            for idx in values:
+                self.__setitem__(idx, values[idx])
+
+    def __setitem__(self, idx, value):
+        if type(idx) is str:
+            if idx in self.labels:
+                self.values[self.labels.index(idx)] = value
+            else:
+                self.labels.append(idx)
+                self.values.append(value)
+        else:
+            self.values[idx] = value
+
+    def __getitem__(self, idx):
+        if type(idx) is str:
+            return self.values[self.labels.index(idx)]
         else:
-            return super(OrderedDict, self).__getitem__(label)
+            return self.values[idx]
 
     def __iter__(self):
-        return self.values().__iter__()
+        return self.values.__iter__()