Stop counting at 10,000 rows when listing tables, refs #2398

datasette/database.py

@@ -29,6 +29,9 @@
 
 
 class Database:
+ # For table counts stop at this many rows:
+ count_limit = 10000
+
  def __init__(
  self,
  ds,
@@ -376,7 +379,7 @@ async def table_counts(self, limit=10):
  try:
  table_count = (
  await self.execute(
- f"select count(*) from [{table}]",
+ f"select count(*) from (select * from [{table}] limit {self.count_limit + 1})",
  custom_time_limit=limit,
  )
  ).rows[0][0]

datasette/templates/database.html

@@ -60,7 +60,7 @@ <h2 id="tables">Tables</h2>
 <div class="db-table">
  <h3><a href="{{ urls.table(database, table.name) }}">{{ table.name }}</a>{% if table.private %} 🔒{% endif %}{% if table.hidden %}<em> (hidden)</em>{% endif %}</h3>
  <p><em>{% for column in table.columns %}{{ column }}{% if not loop.last %}, {% endif %}{% endfor %}</em></p>
- <p>{% if table.count is none %}Many rows{% else %}{{ "{:,}".format(table.count) }} row{% if table.count == 1 %}{% else %}s{% endif %}{% endif %}</p>
+ <p>{% if table.count is none %}Many rows{% elif table.count == count_limit + 1 %}&gt;{{ "{:,}".format(count_limit) }} rows{% else %}{{ "{:,}".format(table.count) }} row{% if table.count == 1 %}{% else %}s{% endif %}{% endif %}</p>
 </div>
 {% endif %}
 {% endfor %}

datasette/views/database.py

@@ -159,6 +159,7 @@ async def database_actions():
  "show_hidden": request.args.get("_show_hidden"),
  "editable": True,
  "metadata": metadata,
+ "count_limit": db.count_limit,
  "allow_download": datasette.setting("allow_download")
  and not db.is_mutable
  and not db.is_memory,
@@ -272,7 +273,7 @@ class QueryContext:
 async def get_tables(datasette, request, db):
  tables = []
  database = db.name
- table_counts = await db.table_counts(5)
+ table_counts = await db.table_counts(100)
  hidden_table_names = set(await db.hidden_table_names())
  all_foreign_keys = await db.get_all_foreign_keys()