Sql statement was ist das SQL ist eine Datenbanksprache zur Definition von Datenstrukturen in relationalen Datenbanken sowie zum Bearbeiten und Abfragen von darauf basierenden Datenbeständen. Die Sprache basiert auf der relationalen Algebra, ihre Syntax ist relativ einfach. 1 SQL ist eine Format-freie Sprache, d.h. wie die Statements optisch aussehen ist prinzipiell völlig gleich. Wie Sätze in einer normalen Sprache bestehen SQL-. 2 Um Werte abzufragen, die innerhalb eines bestimmten Bereichs liegen, helfen folgende Statements: Statement 1 mit Größer/Kleiner. 3 SQL ist die Abkürzung für Structured Query Language, die sich als Standardsprache für die Kommunikation mit zweidimensionalen, relationalen Datenbanken. 4 SELECT Syntax. SELECT column1, column2, FROM table_name; Here, column1, column2, are the field names of the table you want to select data from. If you want to select all the fields available in the table, use the following syntax: SELECT * FROM table_name;. 5 SELECT. SELECT is probably the most commonly-used SQL statement. You'll use it pretty much every time you query data with SQL. It allows you to define what data you want your query to return. For example, in the code below, we’re selecting a column called name from a table called customers. SELECT name FROM customers;. 6 Evaluates the arguments in order and returns the current value of the first expression that initially doesn't evaluate to NULL. For example, SELECT COALESCE (NULL, NULL, 'third_value', 'fourth_value'); returns the third value because the third value is the first value that isn't null. Transact-SQL syntax conventions. 7 Here’s an example of creating a table called Actors with two columns. We also set the ActorId column as the primary key. CREATE TABLE Actors (ActorId INT NOT NULL AUTO_INCREMENT, ActorName VARCHAR () NOT NULL, PRIMARY KEY (ActorId)); See SQL CREATE TABLE for Beginners for more examples. 8 The SQL AND, OR and NOT Operators. The WHERE clause can be combined with AND, OR, and NOT operators. The AND and OR operators are used to filter records based on more than one condition: The AND operator displays a record if all the conditions separated by AND are TRUE. The OR operator displays a record if any of the conditions separated by OR. 9 I'm building a new SQL table and I'm having some trouble with a CASE statement that I can't seem to get my head around. I have two different clauses to be met within the WHEN parameter, separated by an AND clause. Both of these clauses are looking for NULL values, either being null or not null and variations of this. sql einfach erklärt 10 Benutzerdefinierte SQL-Statements dienen dazu, Ihnen komplexe Filterungen in Ihrem Datenbestand zu ermöglichen. Für die Verwendung von SQL-Statements sind. 11 sql w3schools 12