| Data Type |
Built-in type – Choose a predefined data type for the
column. Integers, character strings, and dates are examples of predefined
data types. For some of these types, you can specify size and scale. -
Size – Length of string columns, or the
total number of digits to the left and right of the decimal point
in the result of any decimal arithmetic for numeric columns. For
numeric columns, the size is also called the PRECISION value.
-
Scale – Minimum number of digits after the
decimal point when an arithmetic result is truncated to the maximum
PRECISION value.
-
Units – Unit corresponding to the data
type's size. Possible units include: bits, bytes, characters, or
digits. For CHAR and VARCHAR data types, you can specify the unit
as bytes or characters.
Domain – Choose a domain. A domain is a named
combination of built-in data types, default value, check condition, and
nullability.
Compress values – Compress column values. If a column
is compressed, database server activities such as indexing, data
comparisons, and statistics generation may be slightly slower if they
involve the compressed column because the values must be compressed when
written, and decompressed when read. This option is not available for
certain built-in types.
Maintain BLOB indexes for large values – Maintain
BLOB indexes for large values. Only character, binary, and bit types support
this option.
|
| Value |
No default or computed value – Select this option if
the column is not a computed value and has no default value
Default Value – Select this option if the column has
a default value. If the column is based on a domain, this setting inherits
the domain's default value (if any), but you can override the value for the
column. Choosing the Default value option enables the
User-defined and
System-defined options. -
User-defined – Type a custom value (string,
number, or other expression) for the default value. If you have
based the column on a domain, you can retain the domain's default
value (if any), or override it for the column
-
Literal string – Specify whether the default
value for the column should be treated as a literal string. By
default, this option is selected for character columns and domains
with a character base type. You do not need to enclose default text
in single quotes, and escape embedded single quotes or backslashes
in the string.
-
System-defined – Lets you select a
predefined value (for example, current date) for the default value.
Select a value. If you have based the column on a domain, you can
retain the domain's default value (if any) or override it for the
column.
Partition size – When you select global
autoincrement, the domain of values for that column is partitioned. Each
partition contains the same number of values. For example, if you set the
partition size for an integer column in a database to 1000, one partition
extends from 1001 to 2000, the next from 2001 to 3000, and so on.
Computed Value – Define a computed value for the
column. A computed column derives its values from calculations of values in
other columns. Type an expression in the text box to describe the
relationship between the other columns and the value that appears in the
computed column.
|
| Constraints |
Values can be null – Select this option if null
values are allowed in the column. If the column is based on a domain, you
can retain the domain's nullability or override it for the column.
Values cannot be null – Select this option to allow
duplicate values, but not allow null values in this column.
Values cannot be null and must be unique – Select
this option if values in the column cannot be null and must be unique.
|
| Placement |
Select the placement details for this column – (For
non-global tables within the IQ main store) Select a dbspace. The database
server places the column in the selected dbspace. Only those dbspaces in
read-write mode, and those dbspaces for which the user has permissions,
appear in the list.
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