Client
he operational unit that requests data processing in the client/server model. When a database is used according to the
client/server model, the application program requesting access to the server database operates in the client.
Client/server model
A model used in data processing in which the operational unit (client) that requests data processing and the
operational unit (server) that executes data processing are established separately.
Cluster key
A grouping of columns that become a key for determining the page that stores data. Data for which cluster key values
are equal is stored in the same bucket or overflow part bucket. Cluster keys are specified in the CLUSTER option of a
table DSO definition. If cluster keys are omitted, the primary key of the corresponding table becomes the cluster key.
Column
A constituent element of a table. A relational database represents data using two-dimensional tables consisting of rows
and columns.
Column attribute
Column data types and column constraints
Column constraint
Column constraints include the NOT NULL constraint (NOT NULL) and unique constraints (UNIQUE, PRIMARY KEY).
Related terms:
Unique constraint, NOT NULL constraint
Column name (item name)
The name attached to a column as defined in the schema. The column name is used to specify a column that is the
subject of an operation in an SQL statement that manipulates data.
Commit
Makes the data manipulation of a transaction being processed take effect. The data manipulation in the transaction is
physically reflected in the database. An application program deliberately controls a commit by issuing a COMMIT
statement.
Related term:
Rollback
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