![[*]](footnote.png)
Rim allows the values in a table to be
scaler, vector, and matrix integer or real numbers;
character strings; dates; or times.
The vectors, matrices, and character strings may be of fixed
or variable length.
A table is defined with a fixed number and sequence
of columns. The "conductors" table in
figure ![[*]](crossref.png)
, for example,
is defined with four columns: "Atomic_No.", an integer;
"symbol", a fixed length character string;
"resistivity", a double precision real number;
and "name", a variable length character string.
As data are added to, deleted from, or changed in the
table the number and sequence of rows will vary, but
the number and sequence of the columns will remain the same.
The "conductors" table contains five rows.
The primary advantage of the relational database is its structural simplicity. There is no need for the user to learn the parent-child relationships found in hierarchical databases, nor is there need to understand the pointers of a network database. Data are always represented by simple tables.
![\begin{figure}
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...atabase is shown in figure~\ref{Sample}
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