Getting very very close to postgres working! Just have to fix the nocase statement.

Out of time for a bit, just pushing these up as is for now

Author: jondecker76

examples/tutorial_files/journal_postgres.py

@@ -0,0 +1,68 @@
+import PySimpleGUI as sg
+import pysimplesql as ss                              # <=== PySimpleSQL lines will be marked like this.  There's only a few!
+import logging
+logger=logging.getLogger(__name__)
+logging.basicConfig(level=logging.INFO)               # <=== You can set the logging level here (NOTSET,DEBUG,INFO,WARNING,ERROR,CRITICAL)
+
+
+# -------------------------
+# CREATE PYSIMPLEGUI LAYOUT
+# -------------------------
+# Define the columns for the table selector
+headings=['id','Date:              ','Mood:      ','Title:                                 ']
+visible=[0,1,1,1] # Hide the id column
+layout=[
+    [ss.selector('sel_journal','Journal',sg.Table,num_rows=10,headings=headings,visible_column_map=visible)],
+    [ss.actions('act_journal','Journal')],
+    [ss.record('Journal.entry_date')],
+    [ss.record('Journal.mood_id', sg.Combo, label='My mood:', size=(30,10), auto_size_text=False)],
+    [ss.record('Journal.title')],
+    [ss.record('Journal.entry', sg.MLine, size=(71,20))]
+]
+win=sg.Window('Journal (external)  example', layout, finalize=True)
+
+elephant_postgres = {
+    'host':'queenie.db.elephantsql.com',
+    'user':'yunaahtj',
+    'password':'OMX8u8CDKNVTrldLbnBFsUjxkArTg4Wj',
+    'database':'yunaahtj'
+}
+
+driver=ss.Postgres(**elephant_postgres)
+frm=ss.Form(driver, bind=win)   #<=== Here is the magic!
+# Note:  sql_script is only run if journal.frm does not exist!  This has the effect of creating a new blank
+# database as defined by the sql_script file if the database does not yet exist, otherwise it will use the database!
+
+# Reverse the default sort order so new journal entries appear at the top
+frm['Journal'].set_order_clause('ORDER BY entry_date DESC')
+# Set the column order for search operations.  By default, only the column designated as the description column is searched
+frm['Journal'].set_search_order(['entry_date','title','entry'])
+
+# ---------
+# MAIN LOOP
+# ---------
+while True:
+    event, values = win.read()
+
+    if ss.process_events(event, values):                  # <=== let PySimpleSQL process its own events! Simple!
+        logger.info(f'PySimpleDB event handler handled the event {event}!')
+    elif event == sg.WIN_CLOSED or event == 'Exit':
+        frm.close()              # <= ensures proper closing of the sqlite database and runs a database optimization
+        break
+    else:
+        logger.info(f'This event ({event}) is not yet handled.')
+win.close()
+
+"""
+I hope that you enjoyed this simple demo of a Journal database.  
+Without comments, this could have been done in about30 lines of code! Seriously - a full database-backed
+usable program! The combination of PySimpleSQL and PySimpleGUI is very fun, fast and powerful!
+
+Learnings from this example:
+- Using Query.set_search_order() to set the search order of the query for search operations.
+- creating a default/empty database with an external sql script with the sql_script keyword argument to ss.Form()
+- using Form.record() and Form.selector() functions for easy GUI element creation
+- using the label keyword argument to Form.record() to define a custom label
+- using Tables as Form.selector() element type
+- changing the sort order of Queries
+"""

pysimplesql/pysimplesql.py

@@ -2970,16 +2970,21 @@ def execute_script(self,script):
 # --------------
 try:
     import psycopg2
+    import psycopg2.extras
 except ModuleNotFoundError:
     pass
-class Postgre(SQLDriver):
+
+class Postgres(SQLDriver):
     def __init__(self,host,user,password,database,sql_script=None, sql_commands=None):
         self.host = host
         self.user = user
         self.password = password
         self.database = database
         self.con = self.connect()
 
+        query = "CREATE COLLATION nocase (provider = icu, locale = 'und-u-ks-level2');"
+        self.execute(query)
+
         if sql_commands is not None:
             # run SQL script if the database does not yet exist
             logger.info(f'Executing sql commands passed in')
@@ -3001,14 +3006,16 @@ def connect(self):
         return con
 
     def execute(self, query, values=None):
-        cursor = self.con.cursor(dictionary=True)
+        cursor = self.con.cursor(cursor_factory=psycopg2.extras.RealDictCursor)
         if values:
             cursor.execute(query, values)
         else:
             cursor.execute(query)
+        if len(cursor) == 0: return
+        results = cursor.fetchall()
 
         res=[]
-        for row in cursor:
+        for row in results:
             res.append(row)
 
         lastrowid=cursor.lastrowid if cursor.lastrowid else None
@@ -3025,6 +3032,49 @@ def close(self):
         # Only do cleanup if this is not an imported database
         self.con.close()
 
+    def table_names(self):
+        query = "SELECT table_name FROM information_schema.tables WHERE table_schema='public' AND table_type='BASE TABLE';"
+        #query = "SELECT tablename FROM pg_tables WHERE table_schema='public'"
+        rows = self.execute(query)
+        return [row['table_name'] for row in rows]
+
+    def column_names(self,table):
+        # Return a list of column names
+        query = f"SELECT column_name FROM information_schema.columns WHERE table_name = '{table}'"
+        rows = self.execute(query)
+        return [row['column_name'] for row in rows]
+    def pk_column(self,table):
+        query = f"SELECT column_name FROM information_schema.table_constraints tc JOIN information_schema.key_column_usage kcu ON tc.constraint_name = kcu.constraint_name WHERE tc.constraint_type = 'PRIMARY KEY' AND tc.table_name = '{table}' "
+        cur = self.execute(query)
+        row = cur.fetchone()
+        return row['column_name'] if row else None
+    def relationships(self):
+        # Return a list of dicts {from_table,to_table,from_column,to_column,requery}
+        tables=self.table_names()
+        relationships = []
+        for from_table in tables:
+            query =  f"SELECT conname, conrelid::regclass, confrelid::regclass, confupdtype, "
+            query += f"a1.attname AS column_name, a2.attname AS referenced_column_name "
+            query += f"FROM pg_constraint "
+            query += f"JOIN pg_attribute AS a1 ON conrelid = a1.attrelid AND a1.attnum = ANY(conkey) "
+            query += f"JOIN pg_attribute AS a2 ON confrelid = a2.attrelid AND a2.attnum = ANY(confkey) "
+            query += f"WHERE confrelid = '{from_table}'::regclass AND contype = 'f'"
+
+            rows=self.execute(query, (from_table,))
+            for row in rows:
+                dic = {}
+                # Get the constraint information
+                #constraint = self.constraint(row['conname'])
+                if row['conname'] == 'c':
+                    dic['requery'] = True
+                else:
+                    dic['requery'] = False
+                dic['from_table'] = row['confrelid']
+                dic['to_table'] = row['conrelid']
+                dic['from_column'] = row['referenced_column_name']
+                dic['to_column'] = row['column_name']
+                relationships.append(dic)
+        return relationships
 
 
 # ======================================================================================================================