EDUCBA

EDUCBA

MENUMENU
  • Free Tutorials
  • Free Courses
  • Certification Courses
  • 360+ Courses All in One Bundle
  • Login
Home Data Science Data Science Tutorials SQL Tutorial SQLAlchemy Types
Secondary Sidebar
SQL Tutorial
  • SqlAlchemy
    • What is SQLAlchemy
    • SqlAlchemy ORM
    • SQLAlchemy count
    • SQLAlchemy update object
    • SQLAlchemy pip
    • SQLAlchemy Connection
    • SQLAlchemy Metadata
    • SQLAlchemy Raw SQL
    • SQLAlchemy Filter in List
    • SQLAlchemy Alias
    • SQLAlchemy unique
    • SQLAlchemy JSONB
    • SQLAlchemy Async
    • SQLAlchemy Types
    • SQLAlchemy Many to Many
    • SQLAlchemy Example
    • SQLAlchemy Model
    • SQLAlchemy Data Types
    • SQLAlchemy Filter
    • SQLAlchemy SQLite
    • SQLAlchemy DateTime
    • SQLAlchemy create_engine
    • SQLAlchemy Delete
    • SQLAlchemy Migrations
  • Basic
    • What is SQL
    • Careers in SQL
    • Careers in SQL Server
    • IS SQL Microsoft?
    • SQL Management Tools
    • What is SQL Developer
    • Uses of SQL
    • How to Install SQL Server
    • What is SQL Server
    • SQL Quick References
    • SQL Like Wildcard
    • SQL Like with Multiple Values
    • SQL Examples
    • SQL Server Versions
    • SQL DROP DB
    • SQL Case Insensitive
    • SQL Expressions
    • Database in SQL
    • SQL Data Types
    • SQL Keywords
    • Composite Key in SQL
    • SQL WAITFOR
    • SQL Constraints
    • Transactions in SQL
    • First Normal Form
    • SQL Server Data Types
    • SQL Administration
    • SQL Variables
    • SQL Enum
    • SQL GROUP BY WHERE
    • SQL ROW
    • SQL EXECUTE
    • SQL EXCLUDE
    • SQL Performance Tuning
    • SQL UUID
    • Begin SQL
    • SQL Update Join
    • Cheat sheet SQL
  • Operators
    • SQL Operators
    • SQL Arithmetic Operators
    • SQL Logical Operators
    • SQL String Operators
    • Ternary Operator in SQL
  • Commands
    • SQL Commands
    • sqlplus set commands
    • SQL Alter Command
    • SQL Commands Update
    • SQL DML Commands
    • SQL DDL Commands
    • FETCH in SQL
  • Clause
    • SQL Clauses
    • SQL IN Operator
    • SQL SELECT DISTINCT Multiple Columns
    • SQL Null Values
    • SQL LIKE
    • SQL LIKE Query
    • SQL LIKE Operator
    • SQL LIKE Clause
    • SQL NOT Operator
    • SQL Minus
    • SQL WHERE Clause
    • SQL with Clause
    • SQL HAVING Clause
    • SQL HAVING Clause
    • SQL GROUP BY DAY
    • ORDER BY Clause in SQL
    • SQL ORDER BY CASE
    • SQL ORDER BY DESC
    • SQL ORDER BY DATE
    • SQL ORDER BY Alphabetical
    • SQL ORDER BY Ascending
    • SQL Order by Count
    • SQL GROUP BY Month
    • SQL GROUP BY Multiple Columns
    • SQL GROUPING SETS
  • Queries
    • SQL Insert Query
    • SQL SELECT Query
    • SQL SELECT RANDOM
    • SQL Except Select
    • SQL Subquery
    • SQL SELECT DISTINCT
    • SQL WITH AS Statement
  • Keys
    • SQL Keys
    • SQL Foreign Key
    • Primary Key in SQL
    • Foreign Key in SQL
    • Unique Key in SQL
    • SQL UNIQUE Constraint
    • SQL Primary Key
    • Alternate Key in SQL
    • SQL Super Key
  • Functions
    • SQL Date Function
    • SQL Server Functions
    • SQL String Functions
    • SQL Compare String
    • Timestamp to Date in SQL
    • SQL REGEX
    • SQL Window Functions
    • SQL Syntax
    • SQL CONCAT
    • SQL ALTER TABLE
    • SQL MOD()
    • SQL Timestamp
    • SQL Min and Max
    • SQL TO_DATE()
    • SQL DATEADD()
    • SQL DATEDIFF()
    • SQL HOUR()
    • SQLite? functions
    • ANY in SQL
    • LIKE Query in SQL
    • SQL NOT NULL
    • SQL NOT IN
    • SQL MAX()
    • SQL MIN()
    • SQL SUM()
    • SQL COUNT
    • SQL identity
    • SQL DELETE Trigger
    • SQL Declare Variable
    • SQL Text Search
    • SQL COUNT DISTINCT
    • SQL TEXT
    • SQL Limit Order By
    • BETWEEN in SQL
    • LTRIM() in SQL
    • TOP in SQL
    • SQL Select Top
    • Merge SQL
    • SQL TRUNCATE()
    • SQL UNION
    • SQL ALL
    • SQL INTERSECT
    • SQL Alias
    • SQL Server Substring
    • CUBE in SQL
    • SQL RANK()
    • SQL CTE
    • SQL LAG()
    • SQL MID
    • SQL avg()
    • SQL WEEK
    • SQL DELETE
    • SQL DATEPART()
    • SQL DECODE()
    • SQL DENSE_RANK()
    • SQL NTILE()
    • SQL NULLIF()
    • SQL Stuff
    • SQL Ceiling
    • SQL EXISTS
    • SQL LEAD()
    • SQL COALESCE
    • SQL BLOB
    • SQL ROW_NUMBER
    • SQL Server Replace
    • SQL Ranking Function
    • SQL Server Permission
  • T-SQL
    • T-SQL pivot
    • T-SQL Formatter
    • T-SQL TRY CATCH
    • T-SQL CTE
    • T-SQL CASE
    • T-SQL DATEPART
    • T-SQL Date Format
    • T-SQL ROUND
    • T-SQL Loop
    • T-SQL IIF
    • T-SQL Union
    • T-SQL CREATE TABLE
    • T-SQL INSERT
    • T-SQL Stuff
    • T-SQL ISNULL
    • T-SQL ADD Column
    • T-SQL DATEDIFF
  • Joins
    • Join Query in SQL
    • Types of Joins in SQL
    • Types of Joins in SQL Server
    • SQL Inner Join
    • SQL Join Two Tables
    • SQL Delete Join
    • SQL Left Join
    • LEFT OUTER JOIN in SQL
    • SQL Right Join
    • SQL Cross Join
    • SQL Outer Join
    • SQL Full Join
    • SQL Self Join
    • Natural Join SQL
    • SQL Multiple Join
  • Advanced
    • MDF File in SQL Server
    • SQL Aliases
    • SQL Hosting
    • SQL Auto Increment
    • SQL Injection
    • SQL Wildcards
    • SQL Check
    • SQL Indexes
    • Select Distinct
    • SQL BETWEEN
    • SQLPlus spool
    • SQL Create Table
    • SQL Schema
    • Comparison Operators in SQL
    • SQL_plus
    • SQL Formatter
    • SQL LEFT INNER JOIN
    • SQL Plus Command
    • SQLPlus not found
    • SQL Injection Attack
    • Aggregate Functions in SQL
    • SQL REVOKE
    • SQL Select Distinct Count
    • IF ELSE Statement in SQL
    • SQL CASE Statement
    • SQL While Loop
    • SQL BIGINT
    • SQL Crosstab
    • SQL Wildcard Character
    • SQL INSTR()
    • SQL now
    • SQL synonyms
    • SQLite?export to csv
    • What is Procedure in SQL
    • Stored Procedure in SQL?
    • SQL Server Constraints
    • SQL DELETE ROW
    • Column in SQL
    • Table in SQL
    • SQL Virtual Table
    • SQL Merge Two Tables
    • SQL Table Partitioning
    • SQL Temporary Table
    • SQL Clone Table
    • SQL Rename Table
    • SQL LOCK TABLE
    • SQL Clear Table
    • SQL DESCRIBE TABLE
    • SQL Mapping
    • Cursors in SQL
    • AND in SQL
    • Wildcard in SQL
    • SQL FETCH NEXT
    • SQL Views
    • SQL Delete View
    • Triggers in SQL
    • SQL UPDATE Trigger
    • SQL AFTER UPDATE Trigger
    • SQL Update Statement
    • SQL DROP TRIGGER
    • SQL DROP Table
    • Types of SQL Views
    • SQL Port
    • SQL Clustered Index
    • SQL COMMIT
    • Distinct Keyword in SQL
    • PARTITION BY in SQL
    • SQL Set Operators
    • SQL UNION ALL
    • Metadata in SQL
    • SQL Bulk Insert
    • Array in SQL
    • SQL REGEXP
    • JSON in SQL
    • SQL For loop
    • EXPLAIN in SQL
    • ROLLUP in SQL
    • Escape Character SQL
    • SQL Cluster
    • SQL Backup
    • SQL Pattern Matching
    • SQL Users
    • ISNULL SQL Server
    • SQL pivot
    • SQL Import CSV
    • SQL if then else
    • SQL ignore-case
    • SQL Matches
    • SQL Search String
    • SQL Column Alias
    • SQL extensions
    • SQL Substring Function
    • Charindex SQL
  • NoSQL
    • NoSQL Databases List
    • NoSQL Data Modeling
    • Types of NoSQL Databases
    • NoSQL Injection
    • NoSQL vs SQL Databases
    • NoSQL Use Cases
    • NoSQL Key Value
  • Interview Questions
    • SQL Interview Questions
    • Advance SQL Interview Questions
    • SQL Joins Interview Questions
    • SQL Server Interview Questions
    • SQL Current Month

Related Courses

JDBC Training Course

PHP course

Windows 10 Training

SQL Course Training

PL/SQL Certification Courses

Oracle Certification Courses

SQLAlchemy Types

SQLAlchemy Types

Introduction to SQLAlchemy Types

The SQLAlchemy type is one of the built-in types that can be used for the database, which is the independent data type and one of the basic specific types used to map the application data into the database schema. In addition, it provided the TypeEngines for breaking into the generic types across the multiple database engines, and the dialect-specific types are also handled globally. Specifying the sql datatypes used by each data column of every table when defining the MetaData used with the application is important.

When we can use the unless tables are defined with the autoload=True in which the SQLAlchemy provided the datatypes with the TypeEngines created as the instances provided by the SQLAlchemy classes. When we use python classes, they will be converted to the native database values and vice versa for the TypeEngine objects. Let us use String type as assigned for the special characters like varchar etc. The SQL text is also provided the TypeEngines for using creation or building the tables with the specified metadata and called like a table.create() or create all() methods. We used the application for the SQLAlchemy in the different set of methods that helps to construct the generic type engines with a variety set of database engines. A certain set of databases which further modified with the object conversation from and to the databases, the SQLAlchemy mainly allowed constructing the application with specified custom type engines.

Different Types of SQLAlchemy

It has n number of types, among which some of the SQLAlchemy types are as follows:

1. Built-in Types

It is one of the SQLAlchemy types, and it is mainly provided with fairly basic ideas and is yet to be complete with the TypeEngines for the sql support for additional database column types. We used TypeEngines supported with their corresponding type engines defined in the CLOB. These are derived from the other TypeEngines and may or may not be further specialized with the finer-grained specification of the underlying database types. Here are some of the SQL types, along with the drivers and Arguments mapped with the class name and python type.

Start Your Free Data Science Course

Hadoop, Data Science, Statistics & others

SQLAlchemy Types 1

The above table shows some of the class names like data types mapped to the python types and sql types with the database drivers. We can specify the arguments with the multi-type and single types based on the parameter called by our end.

SQLAlchemy Types 2

The rest of the types, along with the Sql and python types, are for this. It will be used with the TypeEngines to specify the table rows and columns. Some Generic type engines are also imported to the code like SQLAlchemy.types package.

2. Dialect-Specific Types

If we want to generate the dialect-specific content for the sql alchemy, it combines with both generic and dialect-specific type engines. It is also created using the Create Table queries from the generic types. It may be the dialect-specific types in addition to the generic types with some instances. The system uses SQLAlchemy to communicate with various DBAPI implementations and databases. The dialect acts like a factory for the other database-specific object implementation, including the ExecutionContext, complied, default generator, and the TypeEngine. Here, it’s one of some key features with distinct components known as the Core and ORM; the core and the orm sqltoolkit will mainly be abstracted using the smooth layers with an over wide range of DBAPI implementations and behaviors.

Dialect-Specific

SQLAlchemy Types 4

The above diagram shows the list of class names along with the python type and sql type, arguments to connect the database drivers with the parameters.

All in One Data Science Bundle(360+ Courses, 50+ projects)
Python TutorialMachine LearningAWSArtificial Intelligence
TableauR ProgrammingPowerBIDeep Learning
Price
View Courses
360+ Online Courses | 50+ projects | 1500+ Hours | Verifiable Certificates | Lifetime Access
4.7 (86,354 ratings)

3. Generic Types

The generic types packages contain the generic TypeEngines offered by the SQLAlchemy, and it is a wide support range of portable column types. Therefore, we can list the TypeEngines that are more supported to the portable column types, their Python types, and the sql representations. Furthermore, the Type Engines are more defined with all the CLOBs that may or may not be specialized with finer-grained database specification types.

Generic

The TypeEngines are more specified with the table rows and columns with the instance type for the TypeEngine class itself if the default parameters construct the SQL type more.

4. Application-Specific Custom Types

Generally, the SQLAlchemy provides a wide range and set of rich generic database-specific types. However, it is more helpful and widely able to create specific application custom types. Then, for instance, it may wish to emulate the database engine not supported with enumerations type by restricting column values. It contains two types of SQLAlchemy, TypeEngine, and TypeDecorator, for more direct implementation through the TypeEngine subclass.

Whether it may contain already Implementing the TypeDecorator and Creating a New TypeEngine to implement and decorate the TypeEngine subclass.

Examples of SQLAlchemy Types

Given below are the examples of SQLAlchemy Types:

Example #1

Code:

from SQLAlchemy import types
class Firstclasses(types.TypeDecorator):
news=types.Integer
def __init__(a, vars, *al, **cde):
types.TypeDecorator.__init__(a, *al, **cde)
a.vars = vars
def paramsbind(a, value, engine):
outs = a.news.paramsbind(value, engine)
if outs not in a.vars:
raise TypeError(
"The values outss is %s must be one of the output %s" % (outs, a.vars))
return outs
def resout(a, value, engine):
'Have a Nice day thanks for your support'
return a.news.resout(value, engine)
print("Thanks for the first example regarding SQLAlchemy types")

Output:

passing the type called TypeDecorator

The first example is creating the class and passing the type TypeDecorator to convert the inputs to the Integer format, which may be the integer input ranges called numbers. And we defined the set of methods with passing parameters; additionally, we validated the conditions by using the if statement and return and raising the error in TypeError() method. For the same in resout() method and returning the parameters.

Example #2

Code:

from SQLAlchemy import types
class secondclasses(types.TypeDecorator):
second=types.String
def __init__(ab, vars2, *vas, **ref):
types.TypeDecorator.__init__(ab, *vas, **ref)
ab.vars2 = vars2
def newsmeth(ab, vals, eng):
ress = ab.second.newsmeth(value, eng)
if ress not in ab.vars2:
raise TypeError(
"Please find the output results from the newmeth methd" % (ress, ab.vars2))
return ress
def resout(ab, vals, eng):
'Have a Nice day thanks for your support'
return ab.second.resout(vals, eng)
print("Thanks for the second example regarding SQLAlchemy types")

Output:

SQLAlchemy Types 7

In the above example, we used the types like String to convert the values. Here I have mentioned the second class to declare the def type in the rich generic and database-specific types. It is more helpful to create the application with the custom specific types for every instance in the emulate enumerations of the values stored in the database table columns. It generally has two ways to create the application with the specific customer types and implement it for similar existing TypeEngine for the TypeDecorator more involved in the TypeEngine Subclasses.

Conclusion

SQLAlchemy includes many functions, operators, and keywords for connecting database data to the application UI. For example, type is one of the database formats. It operates the table columns from the specified databases and tables previously constructed using the SQLAlchmey with the database drivers.

Recommended Articles

This is a guide to SQLAlchemy Types. Here we discuss the introduction, different types of SQLAlchemy, and examples, respectively. You may also have a look at the following articles to learn more –

  1. SQL ORDER BY DESC
  2. SQL EXECUTE
  3. SQL EXCLUDE
  4. MySQL InnoDB Cluster
Popular Course in this category
JDBC Training (6 Courses, 7+ Projects)
  6 Online Courses |  7 Hands-on Projects |  37+ Hours |  Verifiable Certificate of Completion
4.5
Price

View Course

Related Courses

PHP Training (5 Courses, 3 Project)4.9
Windows 10 Training (4 Courses, 4+ Projects)4.8
SQL Training Program (7 Courses, 8+ Projects)4.7
PL SQL Training (4 Courses, 2+ Projects)4.7
Oracle Training (14 Courses, 8+ Projects)4.7
0 Shares
Share
Tweet
Share
Primary Sidebar
Footer
About Us
  • Blog
  • Who is EDUCBA?
  • Sign Up
  • Live Classes
  • Corporate Training
  • Certificate from Top Institutions
  • Contact Us
  • Verifiable Certificate
  • Reviews
  • Terms and Conditions
  • Privacy Policy
  •  
Apps
  • iPhone & iPad
  • Android
Resources
  • Free Courses
  • Database Management
  • Machine Learning
  • All Tutorials
Certification Courses
  • All Courses
  • Data Science Course - All in One Bundle
  • Machine Learning Course
  • Hadoop Certification Training
  • Cloud Computing Training Course
  • R Programming Course
  • AWS Training Course
  • SAS Training Course

ISO 10004:2018 & ISO 9001:2015 Certified

© 2022 - EDUCBA. ALL RIGHTS RESERVED. THE CERTIFICATION NAMES ARE THE TRADEMARKS OF THEIR RESPECTIVE OWNERS.

EDUCBA
Free Data Science Course

SPSS, Data visualization with Python, Matplotlib Library, Seaborn Package

*Please provide your correct email id. Login details for this Free course will be emailed to you

By signing up, you agree to our Terms of Use and Privacy Policy.

EDUCBA Login

Forgot Password?

By signing up, you agree to our Terms of Use and Privacy Policy.

EDUCBA
Free Data Science Course

Hadoop, Data Science, Statistics & others

*Please provide your correct email id. Login details for this Free course will be emailed to you

By signing up, you agree to our Terms of Use and Privacy Policy.

EDUCBA

*Please provide your correct email id. Login details for this Free course will be emailed to you

By signing up, you agree to our Terms of Use and Privacy Policy.

Let’s Get Started

By signing up, you agree to our Terms of Use and Privacy Policy.

This website or its third-party tools use cookies, which are necessary to its functioning and required to achieve the purposes illustrated in the cookie policy. By closing this banner, scrolling this page, clicking a link or continuing to browse otherwise, you agree to our Privacy Policy

Loading . . .
Quiz
Question:

Answer:

Quiz Result
Total QuestionsCorrect AnswersWrong AnswersPercentage

Explore 1000+ varieties of Mock tests View more