postgres-dynamic 0.0.11

Description:

postgresdynamic 0.0.11

postgres-dynamic - Python-PostgreSQL Dynamic Query Builder
Postgres dynamic is a simple query builder developed for internal usage. It currently supports select, insert, update, and delete statements.
The purpose of this library is for better managament and maintenance of the code used in our environment.
Installation

$ pip install postgres-dynamic

---> 100%


Parameter Format:


connection_object: Callable
connection_object = psycopg2.connect(host,port,database,user,password) #object created from psycopg2.connect()



where: List(dict)
where = [
{
'column_name': 'some_column_name',
'value': 'some_value', # can accept str, int, list, or tuple
'operator': 'some_operator', # can be omitted (accepted operators are =, >, <, >=, <=, IN),
'conjunction': 'some_conjunction', # can be omitted, used when you need to specify more than one conditions and will link with next index value (accepted conjunctions are AND, OR)
},
],



main_table: Union[dict, str]
For select query
main_table = {
'table': 'some_table_name',
'alias': 'some_alias_for_table',
},

For transaction query
main_table = 'some_table_name'



join_table: List(dict)
join_table = [
{
'table': 'some_table_name',
'alias': 'some_alias_for_table',
'join_method': 'join_method', # accepted join methods are (INNER, LEFT, RIGHT, FULL)
'on': 'matching_column_on_both_table',
},
]



column_name: List(str)
column_name = ['some_column_name', 'some_column_name', 'some_column_name',]



column_and_value: dict
column_and_value = {
'some_column_name': 'some_value', # for multiple values just provide more key:value pair
}



order: dict
order = {
'some_column_name': 'ASC', # accepted order values are (ASC, DESC), for multiple order conditions just provide more key:value pair
}



Usage & Code Samples
Example DB
table: employees



id
first_name
last_name




1
Alex
Garcia


2
Joe
Black


3
John
Doe


4
Barry
Allen


5
Charlie
Cox



table: salaries



employee_id
salary




1
120,000


2
135,000


3
150,000


4
180,000


5
120,000





SELECT


Single Select
Single select always return a single value from the query, based on fetchone in psycopg2 and returning a dictionary with {column_name: value} of the tables.

Show more...
Parameters:
main_table #required
where #required
join_table #optional (if omitted it won't join to any table)
column_name #optional (if omitted it will select all columns on the provided table)

Code samples:
# without joining table

from postgres_dynamic import PGDGet
import asyncio

query_result = PGDGet.get_one(
main_table={'table': 'employees'},
where=[
{'column_name': 'id', 'value': '1'},
],
column_name=['first_name']
)

result = asyncio.run(query_result)
print(result)

# {'first_name': 'Alex'}

# with join table salaries

query_result = PGDGet.get_one(
main_table={'table': 'employees', 'alias': 'emp'},
join_table=[
{'table': 'salaries', 'alias': 'sal', 'join_method': 'INNER', 'on': 'emp.id = sal.employee_id'}
],
where=[
{'column_name': 'id', 'value': '1'},
],
)

result = asyncio.run(query_result)
print(result)

# {'id': '1', 'first_name': 'Alex', 'last_name': 'Garcia', 'employee_id': '1', 'salary': 120000}




Multi Select
Multi select always return a dict with key data, based on fetchall in psycopg2 and returning a list of dictionary with {column_name: value} of the tables.
Parameters:

Show more...
main_table #required
where #optional (if omitted no condition will be passed)
join_table #optional (if omitted it won't join to any table)
column_name #optional (if omitted it will select all columns on the provided table)
order #optional (if omitted it won't sort the query)
limit #optional (if a limit count is given, no more than that many rows will be returned but possibly fewer, if the query itself yields fewer rows)
offset #optional (it used to skip that many rows before beginning to return rows)

notes:
- If both OFFSET and LIMIT appear, then OFFSET rows are skipped before starting to count the LIMIT rows that are returned
- When using LIMIT, it is important to use an ORDER BY clause that constrains the result rows into a unique order. Otherwise you will get an unpredictable subset of the query's rows.
- For paging, you can specify 0 or 1 for the starting point of the first page

Code samples:
from postgres_dynamic import PGDGet
import asyncio

query_result = PGDGet.get_all(
main_table={'table': 'employees'},
limit=3,
offset=2
)

result = asyncio.run(query_result)
print(result)

# {'data': [{'id': '4', 'first_name': 'Barry', 'last_name': 'Allen'}, {'id': '5', 'first_name': 'Charlie', 'last_name': 'Cox'}]}






Select count
Select count always return a dict with key total_data, based on SELECT COUNT(*) in SQL and returning a dictionary with {total_data: value} of the query.
Parameters:

Show more...
main_table #required
where #optional (if omitted no condition will be passed)
join_table #optional (if omitted it won't join to any table)

Code samples:
from postgres_dynamic import PGDGet
import asyncio

query_result = PGDGet.get_count(
main_table={'table': 'employees'},
where=[{'column_name': 'first_name', 'value': 'Alex'}]
)

result = asyncio.run(query_result)
print(result)

# {'total_data': 1}






INSERT


Insert Statement
Insert will not return anyting, and will not saved changes to the database unless you specify commit=True in the parameters.

Show more...
Parameters:
main_table #required
column_and_value #required
commit #optional (if omitted, default value will be False which will not saving any changes to database)

Code samples:
# with auto commit

from postgres_dynamic import PGDTransaction
import asyncio

query_result = PGDTransaction.insert(
main_table='employees',
column_and_value={'id': 6, 'first_name': 'Harrison', 'last_name': 'Ford'},
commit=True
)

result = asyncio.run(query_result)
print(result)

# None
# will insert a new employee to the employees table

# without auto commit

query_result = PGDTransaction.insert(
main_table='salaries',
column_and_value={'employee_id': 6, 'salary': 250000},
)

result = asyncio.run(query_result)
print(result)

# None
# will insert a new salary to the salaries table

# save changes to the database
connection_object.commit()






UPDATE


Update Statement
Update will not return anyting, and will not saved changes to the database unless you specify commit=True in the parameters.

Show more...
Parameters:
main_table #required
column_and_value #required
where #required
commit #optional (if omitted, default value will be False which will not saving any changes to database)

Code samples:
# with auto commit

from postgres_dynamic import PGDTransaction
import asyncio

query_result = PGDTransaction.update(
main_table='employees',
column_and_value={'first_name': 'Tyler', 'last_name': 'Oakley'},
where=[
{'column_name': 'id', 'value': '6'},
],
commit=True
)

result = asyncio.run(query_result)
print(result)

# None
# will update employee first_name and last_name with id 6

# without auto commit

query_result = PGDTransaction.update(
main_table='salaries',
column_and_value={'salary': 450000},
where=[
{'column_name': 'employee_id', 'value': '6'},
],
)

result = asyncio.run(query_result)
print(result)

# None
# will update the salary with employee_id 6

# save changes to the database
connection_object.commit()






DELETE


Delete Statement
Delete will not return anyting, and will not saved changes to the database unless you specify commit=True in the parameters.

Show more...
Parameters:
main_table #required
where #required
commit #optional (if omitted, default value will be False which will not saving any changes to database)

Code samples:
# with auto commit

from postgres_dynamic import PGDTransaction
import asyncio

query_result = PGDTransaction.delete(
main_table='salaries',
where=[
{'column_name': 'employee_id', 'value': '6'},
],
commit=True
)

result = asyncio.run(query_result)
print(result)

# None
# will delete salary data with employee_id 6

# without auto commit

query_result = PGDTransaction.delete(
main_table='employees',
where=[
{'column_name': 'id', 'value': '6'},
],
)

result = asyncio.run(query_result)
print(result)

# None
# will delete the employee with id 6

# save changes to the database
connection_object.commit()