Difference between revisions of "User:Alvonruff/Python3"

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There are two major steps to move to python3:
 
There are two major steps to move to python3:
  
 +
* Fix the inconsistent tabs/spaces problem in numerous files (pretty much every file attempted so far). It appears that 8-spaces is far more popular than tabs.
 
* Update to the official MySQL connector. There is no python3 support for MySQLdb, which is our current connector. Moving to a new connector is a prerequisite.
 
* Update to the official MySQL connector. There is no python3 support for MySQLdb, which is our current connector. Moving to a new connector is a prerequisite.
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* Update to python3
+
* Update to python3. This can leverage the futurize work, by removing the "from __future__" lines.
−
 
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* Change the default charset in MySQL
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==MySQL Connector Notes==
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* Repair strings which have URL encodings in MySQL
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To install on python3:
 
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* pip install mysql-connector-python
 
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The connector generates TLS errors with python2.7, as "Python 2.7 support was removed in Connector/Python 8.0.24".
 
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===Instantiating a Connection===
 
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The algorithm using MySQLdb to connect to the database is:
 
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<pre>
 
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    db = MySQLdb.connect(DBASEHOST, USERNAME, PASSWORD, conv=_IsfdbConvSetup())
 
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    db.select_db(DBASE)
 
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    db.set_character_set("latin1")
 
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</pre>
 
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The method using mysql.connector to connect is:
 
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<pre>
 
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    db = mysql.connector.connect(user=USERNAME, password=PASSWORD, host=DBASEHOST, database=DBASE)
 
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</pre>
 
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===Queries That Return a Single Record===
 
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The algorithm using MySQLdb to fetch a single record is:
 
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<pre>
 
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    query = "select author_birthplace from authors where author_id='%d'" % int(authorID)
 
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    db.query(query)
 
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    result = db.store_result()
 
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    record = result.fetch_row()
 
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    return record[0][0]
 
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</pre>
 
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The method using mysql.connector to fetch a single record would be:
 
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<pre>
 
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    query = "select author_birthplace from authors where author_id='%d'" % int(authorID)
 
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    cursor = db.cursor()
 
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    cursor.execute(query)
 
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    record = cursor.fetchone()
 
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    return record[0]
 
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</pre>
 
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===Queries That Return Multiple Record===
 
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The algorithm using MySQLdb to fetch multiple records is:
 
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−
<pre>
 
−
    query = "select pubs.* from pubs,pub_authors where pub_authors.author_id=%d and pubs.pub_id=pub_authors.pub_id;" % aurec
 
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    db.query(query)
 
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    result = db.store_result()
 
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    pub = result.fetch_row()
 
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    results = []
 
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    while pub:
 
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        results.append(pub[0])
 
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        pub = result.fetch_row()
 
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    return results
 
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</pre>
 
−
 
 
−
The method using mysql.connector to fetch a single record would be:
 
−
 
 
−
<pre>
 
−
    query = "select pubs.* from pubs,pub_authors where pub_authors.author_id=%d and pubs.pub_id=pub_authors.pub_id;" % aurec
 
−
    cursor = db.cursor()
 
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    cursor.execute(query)
 
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    results = []
 
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    record = cursor.fetchmany()
 
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    while record:
 
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        results.append(record[0])
 
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        record = cursor.fetchmany()
 
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    return results
 
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</pre>
 

Latest revision as of 19:31, 11 April 2023

There are two major steps to move to python3:

  • Fix the inconsistent tabs/spaces problem in numerous files (pretty much every file attempted so far). It appears that 8-spaces is far more popular than tabs.
  • Update to the official MySQL connector. There is no python3 support for MySQLdb, which is our current connector. Moving to a new connector is a prerequisite.
  • Update to python3. This can leverage the futurize work, by removing the "from __future__" lines.
  • Change the default charset in MySQL
  • Repair strings which have URL encodings in MySQL
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