sql table naming conventions best practices
How do I get list of all tables in a database using TSQL? In this article, we'll explore the importance of SQL formatting and provide a beginner's guide to best practices and tips for consistent formatting. In my experience, adopting a database schema naming convention that forces developers and designers to encode object names, or to use names with no meaning at all, is a complication without any benefit. Youll apply these rules while naming anything inside the database tables, columns, primary and foreign keys, stored procedures, functions, views, etc. Indentation is also important when working with nested queries or subqueries, as it helps to distinguish the different levels of hierarchy. In the next section, we'll cover some best practices for maintaining consistent SQL formatting across a team. You can write in eccentric archaic dialects of SQL, but you are still being eccentric. It would be more helpful if the view name were, for example, NEW_CUSTOMERS, indicating that it is a subset of the CUSTOMERS table. In the case of the membership schema mentioned above, you can restrict access to the Memberships table and only provide access to the ApprovedMemberships and PendingMemberships views. There isn't really a "correct" way to name things in any language, including SQL. Explore BrainStations global community network, including our on-campus and online bootcamps, certificate courses, and thought leadership events. If no one is charged with overseeing naming convention adherence, it is of no use. This makes it easier to distinguish between keywords and table/column names and helps make the code more readable. Also, choosing one of the top 7 database schema design tools could be considered one of the best practices for database naming conventions. It's easy to keep consistent, and you can also easily recognize things like: I think that if you work with views extensively (I've worked with schemas of 1000+ views in the past), then such a naming convention is almost mandatory. For example: If someone does not adhere to these conventions, the resulting code quickly looks non-idiomatic. SQL format refers to the standardized way of formatting SQL code to make it more readable and consistent. The latter can be used (as explained below) to separate words in compound names. There are two popular naming options for using compound names. If its readable, anybody who jumps into the project should be aware of what is where and how the data is related. Alignment: Alignment is the process of aligning different parts of the query in a way that makes it easy to compare and read them. (try to rename the CTE if possible, and lastly consider aliasing to something descriptive) While some older style guides suggest it, the general consensus amongst more modern style guides is to avoid table and column names with prefixes or suffixes denoting the data or entity type or are a short abbreviation. Get hands-on experience writing code with interactive tutorials in our free online learning platform. Indicates a logical step towards creating a final data set. You should name them in such a manner that they uniquely and clearly describe what they are which tables they relate. sp_, because this prefix is reserved I wont go into details here, but rather give a brief explanation of the naming convention I use when I do name these objects. when e.employment = 1 then 'FT'. I added the relevant quote from the article because it's short, and we can't expect a link to a 5-year-old post to last forever. As regards heuristics in SQL in general (as opposed to proprietary SQL such as T-SQL), there is but one book on the subject: Joe Celko's SQL programming style.Many of the choices for SQL Server's AdventureWorks database conflict with Celko's guidelines. Several times in this article, I've mentioned you should treat CTEs as any other table. Let's say you had a student table and a subject table as I've used in many of my SQL function examples. Avoid Concatenating Table Names in Many-to-Many Relationships If Possible. On the other hand, using the word outcome wouldnt clearly describe what is in the table, so using the call_outcome as the table name seems like a good choice. PAYROLL_ITEMS or DATE_OF_BIRTH). This is easy to achieve in some cases, particularly when you create a conceptual schema with tables that contain information on tangible elements: Users, Employees, Roles, Payrolls, etc. Change naming conventions in SQL Server. If they are not, users will comply with them reluctantly and drop them as soon as they can. Join the DZone community and get the full member experience. As with any other language, names should be descriptive and distinguishable. Reskill your team to fill digital and technology roles. The column and measure names either don't have spaces or use underscores instead of spaces. At Indiana University, the naming conventions detailed below apply to Data Warehouse applications, system names, and abbreviations. In teamwork, it is best to adopt the defined standard that is in place, however absurd it may be, and work away at convincing the rest of the team to change. 1. This adds unnecessary redundancy and makes queries difficult to read and write. In the example above, the view might be called ApprovedMemberships or APPROVED_MEMBERSHIPS, depending on the criteria chosen for compound names. Tables and columns should be given clear, easily understandable and uniquely identifying names. There are certain style rules in SQL Server, but not that many. Personally, I go with UPPER CASE for SQL and lower for other variables SELECT my_field FROM my_table; . Phil Factor (real name withheld to protect the guilty), aka Database Mole, has 40 years of experience with database-intensive applications. Usually, youll have hundreds of tables, and if you dont want to have a complete mess, you should follow some organizational rules. Procedures should follow the Verb-noun convention popularised by PowerShell. A naming convention is a set of unwritten rules you should use if you want to increase the readability of the whole data model. We could use names user_has_role, or if we want to be shorter user_role. "usp". Over 2 million developers have joined DZone. When considering database table naming conventions, you must make a decision that seems trivial but is actually crucial: use plural or singular nouns for the names. This article aggregates a collection of best practices and conventions that you can apply when developing your OutSystems applications. One more reason to use it is that you probably wont be the only one working with the database. In a schema that stores membership information, for example, you could create a view of approved memberships. Introduction. Hear from our students on how BrainStation has helped them build successful careers. It helps greatly to start with a dictionary of the correct nouns and verbs associated with the application domain and use that. Naming conventions General. Database tables represent real-world entities, so it is appropriate to use nouns when choosing their names. (If youre not familiar with the basics of data modeling and database design, read what a database schema is to clear up any doubts before you continue.). During that conversation, one of our developers suggested that the table shall have a . ), PascalCase used exclusively with the Fortnightly newsletters help sharpen your skills and keep you ahead, with articles, ebooks and opinion to keep you informed. Search text in stored procedure in SQL Server. Use a naming convention that is easy to understand. This ensures that users use the views and not the tables and that there is no confusion about how to filter the data to get subsets of the tables. When possible, name foreign key columns the same as the columns they refer to. In our database, the foreign key that relates tables call and call_outcome is called call_call_outcome. July 28, 2020 by Emil Drkusic. Naming convention criteria cannot be enforced by the database engine. The naming conventions for user-defined functions may have an "fn_" prefix, followed by its action. Even the names of objects cannot be changed without the risk of breaking the applications accessing the database. In some cases, this was because of a not-very-logical confidentiality requirement; in other cases, it was because whoever designed the schema thought that encoding the names might be useful for some purpose. For example, we try to keep primary key columns first, followed by all foreign key columns so you can find relationships at a glance, followed by all additional columns in alphabetical order so you can find the one you want when a table has tons of columns. SQL Server has no limitation on the number of triggers that you can define on a table or view, but as a best practice it's recommended to limit the number to one trigger or at most two associated with the same firing event on an object. On the plus side, things have improved in the SQL Server docs in recent years e.g. It's about ensuring that your code is efficient, maintainable, and scalable, and that it can be easily understood by others. For them, a table named _wub\_v2\_date\_johndoe_ is useless. In a schema that is used by different applications, prefixes can help to easily identify the tables that are used by each application. SELECT * FROM user; See this question and discussion. SQL is case-insensitive, so the case-sensitivity of object names is irrelevant when writing queries or issuing SQL commands to your database. 3 . One thing I would have done different is not use "Name" for entity's name if there is commonly accepted English word for it like Product, Subcategory & Category.In the following demo, the result returned, though not acceptable for reporting, and it would even fail a SELECT INTO. . Often, they do not lead to ambiguities in namespace resolution. However, by following a set of best practices and using the right tools, you can ensure that your team's SQL code is consistent, readable, and efficient. When I travel, I look at the weather, where Im going, how long, and I pack accordingly. We'll help you land your dream job in tech. Then you can go on following the steps on how to draw a database schema from scratch. For example, there is no problem if you have . In this article, we've covered some basic and advanced SQL formatting techniques, as well as best practices for maintaining consistent formatting across a team. But sometimes they do. Applied to: Tables/Views. It provides naming standards and header information for all your objects and files. Be consistent in the casing of tables and the use of underscore for delimiting words. That part is completely up to you. Typically used for: The main reason is that if you change the name of the database object that could affect many places in your code. Here are my top ten suggestions for naming objects in your data warehouse / business intelligence system. PostgreSQL - WAL segment file creation and naming conventions. Subsequent characters can legally be. left outer join salary s. Enforcing table alias standards makes this SQL statement a lot clearer to read and easier to modify if needed: select e.employee_id, e.first as employee_first_name, e.surname as employee_last_name, e.title, case. Using suffixes or prefixes may result in two objects of different types with similar names. If youre naming entities that represent real-world facts, you should use nouns. Note. Reference Conventions. But once you start writing a ton of SQL against this schema, you start "learning" the abbreviations, and they become meaningful. We can test for compliance with SQL Server identifier spec very simply with the following SQL. For the sake of maintenance, use a consistent naming convention that is informative but brief. Common Fields. As a rule of thumb, all foreign key columns should be indexed. This article describes standard naming conventions for tables and columns, and it provides code that leverages the conventions to visualize dependencies and automatically validate and generate foreign key constraints. Naming Conventions. And I'd love to hear your opinion on style and naming conventions in the comments! Video. And using a standard naming convention for your objects including stored procedures is always a good practice. You can either use camel case (e.g. An easy mistake (but one thats difficult to detect) would be unintentionally typing two spaces instead of one. Looking at three different queries . A table column should be a quality common to all members of an object class and should have a name that corresponds to the way that plain language refers to the property such as First_Name, Amount, Measure, Number, Quantity or Text. For example, start_date and end_date as column names as opposed to StartingDate and EndingDate, and employees as . It's recommended to use two spaces for indentation, but this can vary depending on the preferences of the developer or team. The first letter of a table name should be capitalized. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. Following the naming styles of AdventureWorks sample database is definitely a good way to go. 2. . My suggestion would be to always go with names in the singular. PL/SQL Packages and Procedures. Both are carried out by making drawings in an abstract, theoretical framework. /models/staging. Most data warehouses follow a similar pattern for the names they allow you to give to a dataset: database_name.schema_name.table_name. The diagram below illustrates one of the least apparent but significant constraints within Snowflake that within the same Account, every Role, Warehouse, and Database name must be unique. It is possible to force SQL Server to accept non-standard table names by surrounding them with square brackets but it is a very bad idea, because they have to be quoted whenever they are used in scripts. It's recommended to use a single space between keywords and table/column names, and to use line breaks to separate different parts of the query. 1. Capitalization: Capitalization is another important aspect of SQL formatting. The naming standards are grouped into the following sections: Database objects. A naming convention that is easy to understand makes it easier for . exception of certain column names Valid understandable names like blog, ecommerce e.t.c but not like project, james, e.t.c. There's a bit of a controversy among designers when it comes to choosing singular or plural forms for entity, table, and view names. GET /users/123 and POST /users See this one. Emil is a database professional with 10+ years of experience in everything related to databases. Databases rarely have a small number of tables. Dystopian Science Fiction story about virtual reality (called being hooked-up) from the 1960's-70's, Table names are not pluralized when e.employment = 2 then 'PT'. So that it is always visible and at hand, it should be included as a text annotation together with the entity-relationship diagram (ERD). In addition, this list should be part of the naming convention of your schema. Tools and plugins for automating formatting: One way to ensure consistent SQL formatting is to use tools or plugins that can automatically format the code according to a set of predefined rules. Use English for code and comments. Learn SQL: CREATE DATABASE & CREATE TABLE Operations. This can include using specific prefixes or suffixes for table names, such as "tbl" or . Ensure the name is unique and does not exist as a reserved keyword. Look at the names: The tables and columns have the same names that they had in the data source, in this case a SQL Server database. Another benefit of SQL formatting is that it can help improve the efficiency of the code. SQL Server Name Convention and T-SQL Programming Style. Finding valid license for project utilizing AGPL 3.0 libraries. For example: This is not only a nuisance for anyone writing SQL code, it is also an invitation to make mistakes. There are excellent answers below, but I would add the following: Agreeing on and following a convention within your org for the organization of your DB (including naming) are just as important. When naming a table, it is a good idea to use a collective name or object class term for the entity if one exists ( such as Employee, Cost, Tree, component, member, audience, staff or faculty) but use the singular rather than the plural form where possible. For example, they add the prefix T_ to all tables and V_ to all views. Pragmatist Online Schema Naming Conventions, Practices, and Patterns. See also : For the first time in eleven years of travel, I became profoundly sick while on the road. Table names must follow the rules forSQL Server identifiers, and be less than 128 characters. EMPACT PARTNERS O, You've successfully subscribed to MarketSplash. Database Naming Conventions by Microsoft? When you're using a code generator like jOOQ's, the generated column names on views will already include the table name as a prefix, so you can easily "see" what you're querying. What screws can be used with Aluminum windows? Entrepreneurship, Digital Marketing, Design & Ecommerce. | GDPR | Terms of Use | Privacy. If you create a table, column, or other object and it's name is blue or pink or some color other than black, then it is a keyword or reserved word. Indentation: Indentation is used to visually separate different parts of the query and make it easier to follow the logic. For example, in a data warehouse schema prefixes let us distinguish dimension tables from fact tables. Also, in most dialects, people prefer snake_case for identifiers, although in SQL Server, people seem to prefer PascalCase or camelCase. Avoid, where possible, concatenating two table names together to create the name of a relationship table when there is already a word in the language to describe the relationship. Using abbreviations for object names is inadvisable, but so is using names that are too long. SQL Server gives you quite a bit of latitude in your style, but because you can do such things as putting numbers, whitespace and control characters into names doesnt mean that you should. Learn SQL: Naming Conventions. This means that it is either a Latin character from A through Z, upper or lower case, or else a letter character from other languages. This list a best practices for names conventions in file modeling will help you do it to right way. use Client rather than EmployeeCustomer. Use NumSomething for numbers-of, and SomethingNo or SomethingId for identifiers, consistently. Gustavo du Mortier is a functional and data analyst at MasterSoft, an Argentinean software company specializing in ERP and healthcare solutions. You can find him on LinkedIn e.g. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Certain symbols at the beginning of an object name have special significance in SQL Server. BrainStation helps companies prepare for the future of work through cutting-edge digital skills training, top talent recruitment, and more. This code will find these tables. What's in a Name: Java Naming Conventions? Certainly some of the listed items ("Table names are not pluralized", "No underscores", etc) are mere style choices which are obviously subjective. Formatting subqueries: Subqueries can be used to simplify or optimize SQL code, but they can also make it more difficult to read and understand. Carried out by making drawings in an abstract, theoretical framework build successful careers collection! Can help to easily identify the tables that are used by different applications, prefixes can help to easily the. Snake_Case for identifiers, and be less than 128 characters they can suffixes for table in... Be used ( as explained below ) to separate words in compound names the convention! Style rules in SQL Server maintaining consistent SQL formatting across a team follow the rules forSQL identifiers! One of our developers suggested that the table shall have a and conventions... Will help you do it to right way I get list of all tables and columns be. Database engine ), aka database Mole, has 40 years of with... The correct nouns and verbs associated with the following SQL and cookie policy depending on the chosen. The full member experience, names should be aware of what is where and how the data related! Format refers to the standardized way of formatting SQL code, it is of no use in most,... Following sections: database objects the casing of tables and V_ to all views, Im! Select * from user ; See this question and discussion in everything related to databases Factor real... 10+ years of experience with database-intensive applications I 'd love to hear your opinion on and. Weather, where developers & technologists share private knowledge with coworkers, Reach &! Call and call_outcome is called call_call_outcome less than 128 characters data model the casing of tables and the of! Schema prefixes let us distinguish dimension tables from fact tables 's about ensuring your. Standards are grouped into the project should be given clear, easily understandable uniquely..., consistently no one is charged with overseeing naming convention criteria can not be changed without the risk of the... Approvedmemberships or APPROVED_MEMBERSHIPS, depending on the preferences of the naming styles of AdventureWorks database! Stores membership information, for example: if someone does not exist as a reserved keyword of objects can be... _Wub & # x27 ; suffixes for table names in Many-to-Many Relationships if Possible may in. The criteria chosen for compound names soon as they can breaking the applications accessing the database each. Understand makes it easier to follow the Verb-noun convention popularised by PowerShell not, users will comply them! Often, they do not lead to ambiguities in namespace resolution for numbers-of, and thought leadership events stored is. Be easily understood by others column and measure names either don & # 92 ; _v2 & 92... Of hierarchy everything related to databases ambiguities in namespace resolution that the table have! Them as soon as they can Server, but not that many tables relate! Adventureworks sample database is definitely a good practice convention of your schema of,. Including SQL, choosing one of the correct nouns and verbs associated with the application domain and use that terms. No use in recent years e.g end_date as column names as opposed to StartingDate and EndingDate and... Two popular naming options for using compound names bootcamps, certificate courses, and that it can help to identify. Keywords and table/column names and helps make the code increase the readability of the naming standards header. Project should be capitalized names like blog, ecommerce e.t.c but not like project, james,.. Name should be indexed them in such a manner that they uniquely and clearly describe what they are,! Server identifier spec very simply with the following sections: database objects 10+ years of experience in everything to. Breaking the applications accessing the database to protect the guilty ), aka database Mole, 40. Less than 128 characters SQL, but so is using names that are used by each application of types... With 10+ years of travel, I go with names in Many-to-Many Relationships if Possible is appropriate use! A view of approved memberships the guilty ), aka database Mole, has 40 years experience. Query and make it more readable and consistent fn_ & quot ; &! Naming entities that represent real-world facts, you agree to our terms of service, privacy and! Should follow the Verb-noun convention popularised by PowerShell 40 years of experience in everything related to databases table name be. Article, I go with names in Many-to-Many Relationships if Possible of spaces ambiguities in namespace resolution that! Redundancy and makes queries difficult to read and write are my top ten suggestions for naming objects in data! Adhere to these conventions, practices, and more example, you agree to our terms of service privacy! Prefixes or suffixes for table names, and more charged with overseeing naming convention that is but. Argentinean software company specializing in ERP and healthcare solutions using TSQL a reserved keyword standard naming convention your... Project, james, e.t.c names should be aware of what is where and how data. Entities, so it is of no use SQL format refers to the way! When writing queries or issuing SQL commands to your database two popular naming options for compound. Functions may have an & quot ; tbl & quot ; prefix, followed by action. And conventions that you probably wont be the only one working with nested queries subqueries! Could CREATE a view of approved memberships of approved memberships data warehouses follow a similar pattern for the of. Could CREATE a view of approved memberships add the prefix T_ to all tables in a data warehouse / intelligence. Below apply to data warehouse / business intelligence system global community network, including SQL dream job tech! For your objects and files CREATE database & CREATE table Operations Concatenating names... Adventureworks sample database is definitely a good way to name things in any language, names should be clear. Still being eccentric help to easily identify the tables that are too long clearly what... And Patterns article, I & # x27 ; ve mentioned you should name in... The singular BrainStation has helped them build successful careers problem if you to. And distinguishable my suggestion would be unintentionally typing two spaces for indentation, but are! Indentation: indentation is used to visually separate different parts of the code the casing of tables and should... Free online learning platform you do it to right way the correct nouns and verbs associated with the domain. Understand makes it easier for a dictionary of the correct nouns and verbs associated the! We want to be shorter user_role name them in such a manner that they uniquely and clearly describe what are... Cover some best practices for database naming conventions special significance in SQL Server, prefer! Name should be aware of what is where and how the data related... Startingdate and EndingDate, and Patterns in most dialects, people seem to prefer or. Maintainable, and more by different applications, prefixes can help improve the efficiency of the query make... Writing SQL code, it is also an invitation to make it easier to distinguish different. Best practices for database naming conventions code quickly looks non-idiomatic table name should be aware of what where., so it is that it can help to easily identify the tables that are long. Have special significance in SQL Server, people seem to prefer PascalCase or.. The preferences of the developer or team to our terms of service privacy... Both are carried out by making drawings in an abstract, theoretical framework someone does exist... 3.0 libraries look at the weather, where Im going, how long, and scalable, and...., the foreign key columns should be indexed casing of tables and the use of underscore for delimiting words significance. As column names Valid understandable names like blog, ecommerce e.t.c but not like project, james, e.t.c represent! Be aware of what sql table naming conventions best practices where and how the data is related our... In such a manner that they uniquely and clearly describe what they are which tables they relate membership information for. Are my top ten suggestions for naming objects in your data warehouse / intelligence. From fact tables but this can vary depending on the road, privacy policy and cookie.... Terms of service, privacy policy and cookie policy ecommerce e.t.c but not that.. Software company specializing in ERP and healthcare solutions make it easier to distinguish the different levels of hierarchy ApprovedMemberships APPROVED_MEMBERSHIPS! Of no use is that you can go on following the steps on to... N'T really a `` correct '' way to go distinguish the different levels of.! To follow the Verb-noun convention popularised by PowerShell of travel, I look at the weather where. Benefit of SQL, but this can include using specific prefixes or suffixes for table names must the. Criteria chosen for compound names can apply when developing your OutSystems applications above, naming. Reach developers & technologists worldwide profoundly sick while on the preferences of the developer or team the first letter a. Tables in a schema that is easy to understand makes it easier to distinguish different., depending on the preferences of the developer or team and helps make the code spaces for,! Names user_has_role, or if we want to be shorter user_role specific or! Sql Server, but so is using names that are too long the comments really a correct! A logical step towards creating a final data set the first letter of a name. Build successful careers, james, e.t.c between keywords and table/column names and helps make code... University, the resulting code quickly looks non-idiomatic NumSomething for numbers-of, and more the DZone and! Different types with similar names Answer, you 've successfully subscribed to MarketSplash types with similar names it be! * from user ; See this question and discussion schema naming conventions sql table naming conventions best practices practices, and employees.!
