In SQL, null or NULL is a special marker used to indicate that a data value does not exist in the database. Introduced by the creator of the relational...
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light Null (SQL) (or NULL), a special marker and keyword in SQL indicating that a data value does not exist, is not known, or is missing. Null character...
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department. These are the SQL statements to create the above tables: CREATE TABLE department( DepartmentID INT PRIMARY KEY NOT NULL, DepartmentName VARCHAR(20)...
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anything with Null directly, SQL provides two Null-specific comparison predicates: IS NULL and IS NOT NULL test whether data is or is not Null. SQL does not...
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Data definition language (redirect from Drop (SQL))
In the context of SQL, data definition or data description language (DDL) is a syntax for creating and modifying database objects such as tables, indices...
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concatenation, NULLs, and comparison case sensitivity vary from vendor to vendor. PostgreSQL and Mimer SQL strive for standards compliance, though PostgreSQL does...
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"NUL") Null sign (∅), the empty set Null (SQL) (ω), a special marker and keyword NULL in SQL Empty string (λ, Λ, or ε), in formal language theory Null (disambiguation)...
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defined to be NULL or not. The ANSI SQL-92 standard includes the COALESCE function implemented in Oracle, SQL Server, PostgreSQL, SQLite and MySQL. The COALESCE...
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Boolean data type (section SQL)
In SQL, which uses a three-valued logic for explicit comparisons because of its special treatment of Nulls, the Boolean data type (introduced in SQL:1999)...
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PL/SQL (Procedural Language for SQL) is Oracle Corporation's procedural extension for SQL and the Oracle relational database. PL/SQL is available in Oracle...
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(T879–T882) Various smaller changes to the existing SQL language (all optional features): UNIQUE null treatment (F292) ORDER BY in grouped table (F868)...
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Microsoft SQL Server is a proprietary relational database management system developed by Microsoft using Structured Query Language (SQL, often pronounced...
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letters or typographic symbols) but not data marks (also known as NULL marks in SQL world). Morphologically, a composite primary key is in a "steady state":...
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certain comparisons with NULL values. Proper use of these advanced conditions enhances the flexibility and robustness of SQL queries, particularly in...
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reserved. SQL SQL syntax List of relational database management systems Page listing all reserved words in the SQL standard, from SQL-92 to SQL:2016: Standard...
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database management system (RDBMS) emphasizing extensibility and SQL compliance. PostgreSQL features transactions with atomicity, consistency, isolation,...
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database, as in NULL in SQL. In other words, NULL is undefined. Primitive types such as integers and Booleans cannot generally be null, but the corresponding...
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Customers ( Id CHAR(12) NOT NULL PRIMARY KEY, Surname VARCHAR(32) NOT NULL, FirstName VARCHAR(32) NOT NULL, DOB DATE NOT NULL # DOB: Date of Birth ); SELECT...
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Stored procedure (section Comparison with static SQL)
introduction of procedural elements to the SQL language in the SQL:1999 and SQL:2003 standards in the part SQL/PSM. That made SQL an imperative programming language...
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Unique key (section Defining keys in SQL)
UNIQUE constraints on nullable columns but the SQL standard states that the constraint does not guarantee uniqueness of nullable columns (uniqueness is...
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Referential integrity (section Meaning in SQL)
languages—SQL Part 1: Framework (SQL/Framework) Part 2: Foundation (SQL/Foundation) Chigrik, Alexander (2003-08-13). "Managing Users Permissions on SQL Server"...
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Primary key (section Defining primary keys in SQL)
the SQL Standard, primary keys may consist of one or multiple columns. Each column participating in the primary key is implicitly defined as NOT NULL. Note...
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keys, unique indexes, CHECK constraints, and NOT NULL constraints). In some databases, such as PostgreSQL, when a FROM clause is present, what essentially...
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C Sharp 2.0 (section Nullable value types)
improved interaction with SQL databases, which can have nullable columns of types corresponding to C# primitive types: an SQL INTEGER NULL column type directly...
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Ophelia| | Nick| Ophelia| Zach| | Ophelia| Zach| (null)| Window functions were incorporated into the SQL:2003 standard and had functionality expanded in...
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Adaptive Server Enterprise (redirect from Sybase SQL Server)
SAP ASE (Adaptive Server Enterprise), originally known as Sybase SQL Server, and also commonly known as Sybase DB or Sybase ASE, is a relational model...
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from SQL storage") } user, err = uc.storage.Get(r.Context(), "johndoe") if err != nil { uc.log.Error().Err(err).Msg("Error getting user from SQL storage")...
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A hierarchical query is a type of SQL query that handles hierarchical model data. They are special cases of more general recursive fixpoint queries, which...
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Prepared statement (redirect from Prepare (SQL))
confused with parameterized query) is a feature where the database pre-compiles SQL code and stores the results, separating it from data. Benefits of prepared...
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List of tools for static code analysis (section PL/SQL)
"Visual Expert for Oracle - PL/SQL Code Analyzer". www.visual-expert.com. 2017-08-24. "Visual Expert for SQL Server - Transact SQL Code Analyzer". www.visual-expert...
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