Rename "print" to "view"

Add print Implement limit for view

Author: jferard

README.rst

@@ -103,6 +103,8 @@ Save the result of the last select to a csv file:
 
  $export file.csv
 
+If the result was already fetched, the query is rerun.
+
 ``def``
 -------
 To use a custom python function in the script:
@@ -113,9 +115,28 @@ To use a custom python function in the script:
  ...
  return ret
 
+``view``
+--------
+Print the result of the last select on the terminal:
+
+.. code:: sql
+
+ $view [limit]
+
+An optional argument ``limit`` sets the maximum number of rows to display. If ``limit`` is omitted, the its value is ``100``. If ``limit == -1``, then no limit is set.
+
+If the result was already fetched, the query is rerun.
+
+``print``
+---------
+Print a string or a list of string on the terminal
+
+.. code:: sql
+
+ $print something
+
 TODO
 ====
 * A ``script`` instruction that stores the session
-* A ``print`` instruction that prints the result of the last query
 * A ``dump`` instruction to dump the in memory database
 * An ``aggregate`` to create aggregate functions

examples/example.sql

@@ -53,6 +53,12 @@ ORDER BY SUM(amount) DESC
 
 $export "by_state.csv"
 
-$print
+$print "The content of by_state.csv is:"
+
+$view -1
+
+$print "The first 10 lines of by_state.csv are:"
+
+$view 10
 
 DROP VIEW IF EXISTS detailed

sqliteondbf.py

@@ -102,7 +102,7 @@ def __init__(self, script, logger):
  else:
  self.__script = script.read()
  self.__logger = logger
- self.__ex = {"connect":self.__connect, "convert":self.__convert, "export":self.__export, "def":self.__def, "print":self.__print}
+ self.__ex = {"connect":self.__connect, "convert":self.__convert, "export":self.__export, "def":self.__def, "print":self.__print, "view":self.__view}
 
  def __connect(self, e, t, fpath, encoding="cp850"):
  self.__logger.info("set source to {} ({})".format(fpath, t))
@@ -138,19 +138,17 @@ def __def(self, e, *args):
 
  self.__connection.create_function(name, len(params), func)
 
- def __print(self, e, *args):
+ def __view(self, e, *args):
  self.__ensure_cursor()
 
  if args:
- limit = args[0]
+ limit = int(args[0])
  else:
  limit = 100
+ view(self.__cursor, limit, self.__logger)
 
- column_names = [description[0] for description in self.__cursor.description]
- rows = [r for _, r in zip(range(limit), self.__cursor)]
- ws = [max(len(str(y)) for y in col) for col in zip(column_names, *rows)]
- for zs in (column_names, *rows):
- print ("\t".join([str(z).rjust(w) if type(z) in (int, float) else str(z).ljust(w) for z, w in zip(zs, ws)]))
+ def __print(self, e, *args):
+ print (*args)
 
  def __ensure_cursor(self):
  if self.__cursor_fetched:
@@ -237,6 +235,19 @@ def export(cursor, csv_path, logger=logging.getLogger("sqliteondbf")):
  for row in cursor:
  writer.writerow(row)
 
+def view(cursor, limit, logger=logging.getLogger("sqliteondbf")):
+ logger.debug("display data on terminal")
+ column_names = [description[0] for description in cursor.description]
+ if limit >= 0:
+ rows = [r for _, r in zip(range(limit), cursor)]
+ else:
+ rows = [r for r in cursor]
+ ws = [max(len(str(y)) for y in col) for col in zip(column_names, *rows)]
+ for zs in (column_names, *rows):
+ print ("\t".join([str(z).rjust(w) if type(z) in (int, float) else str(z).ljust(w) for z, w in zip(zs, ws)]))
+ if cursor.fetchone():
+ print ("...")
+
 
 if __name__ == '__main__':
  main()