What is a column in a database called?
In the context of a relational database, a row—also called a tuple—represents a single, implicitly structured data item in a table. In simple terms, a database table can be thought of as consisting of rows and columns. Each column expects a data value of a particular type.
A column-oriented DBMS (or columnar database management system) is a database management system (DBMS) that stores data tables by column rather than by row. Practical use of a column store versus a row store differs little in the relational DBMS world.
- Cassandra is a partitioned row store. Cassandra will automatically repartition as machines are added and removed from the cluster. Row store means that like relational databases, Cassandra organizes data by rows and columns. Column oriented or columnar databases are stored on disk column wise.
- A column family is a database object that contains columns of related data. It is a tuple (pair) that consists of a key-value pair, where the key is mapped to a value that is a set of columns. In analogy with relational databases, a column family is as a "table", each key-value pair being a "row".
- In the context of a relational database, a row—also called a tuple—represents a single, implicitly structured data item in a table. In simple terms, a database table can be thought of as consisting of rows and columns. Each column expects a data value of a particular type.
Column names. The meaning of a column name depends on its context. A column name can be used to: Declare the name of a column, as in a CREATE TABLE statement. In a GROUP BY or ORDER BY clause, a column name specifies all values in the intermediate result table to which the clause is applied.
- The use of table aliases is to rename a table in a specific SQL statement. The renaming is a temporary change and the actual table name does not change in the database. The column aliases are used to rename a table's columns for the purpose of a particular SQL query.
- The SQL IN condition (sometimes called the IN operator) allows you to easily test if an expression matches any value in a list of values. It is used to help reduce the need for multiple OR conditions in a SELECT, INSERT, UPDATE, or DELETE statement.
- Click the letter of the column you want to change and then click the "Formulas" tab. Click "Define Name" in the Defined Names group in the Ribbon to open the New Name window. Enter the new name of the column in the Name text box.
Updated: 2nd October 2019