This MySQL Create Database lesson is for a beginner. Read the short notes, run each example, then change one name or number and run it again.
CREATE DATABASE adds a new database on the server. You then connect to that name before you create tables.
The example stands in for that step by naming a container for later tables.
Example 1: Start here
The SQL is CREATE DATABASE training. You need permission on the server to run it.
databases = {} # a dictionary; each key has one value
databases["training"] = {} # change this one field
print(sorted(databases)) # a new list, sorted
Example 2: Filter the rows
MySQL Create Database is easier to see as a list of records. The filter keeps every row whose seats value is at least 10.
rows = [{"topic": "MySQL Create Database", "seats": 14}, {"topic": "SQL", "seats": 12}] # a list; the values stay in this order
print([row["topic"] for row in rows if row["seats"] >= 10]) # keep the items that pass the test
Example 3: Update one field
An update changes one field and leaves the rest of the record alone. On a database you would run an UPDATE or an update_one for the same change.
row = {"topic": "MySQL Create Database", "seats": 14} # a dictionary; each key has one value
row["seats"] = row["seats"] + 1 # change this one field
print(row)
Example 4: Count the matches
Counting matches is the idea behind COUNT(*). Here the number 14 appears twice.
rows = [14, 4, 14] # a list; the values stay in this order
print(sum(1 for value in rows if value == 14)) # keep the items that pass the test
The SQL is CREATE DATABASE training. You need permission on the server to run it.
