SQL/MP Reference Manual

HP NonStop SQL/MP Reference Manual—523352-013
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ICOMPRESS File Attribute
ICOMPRESS is a file attribute that controls key compression in index blocks.
ICOMPRESS applies only to key-sequenced tables and indexes.
The table default is NO ICOMPRESS.
The index default is the table value at index creation.
Considerations—ICOMPRESS

Occasionally, the use of ICOMPRESS can reduce the number of index levels.
Reducing the number of index levels improves performance.
You can check the number of index levels by looking at the INDEXLEVELS column
of the INDEXES catalog table. (ALTER INDEX does not update the INDEXLEVELS
column but UPDATE STATISTICS does.) If ICOMPRESS does not reduce index
levels, it lowers performance but saves disk space.

The disk process does a sequential scan of all indexes in the block, beginning at
the start of the block. This function is similar to DCOMPRESS; savings result when
the index contains many like values.

Relative and entry-sequenced tables always have the NO ICOMPRESS attribute,
but index block compression has no meaning for them.
IF/THEN/ELSE Clause
IF/THEN/ELSE is an SQLCI report writer clause that specifies a condition for printing
one or the other of two print lists. It works in the BREAK FOOTING, BREAK TITLE,
DETAIL, PAGE FOOTING, PAGE TITLE, REPORT FOOTING, and REPORT TITLE
commands.
You can nest IF/THEN/ELSE clauses.
cond-expr
is a conditional expression that determines whether the THEN clause or the ELSE
clause contains the list to print.
The conditional expression has the same form as an SQL search condition, except
that it cannot include subqueries. It can include any form of column name (for
example, COL 3 > 5 or EMPNUM = 228). Numeric expressions within the
{ ICOMPRESS | NO ICOMPRESS }
IF cond-expr THEN (print-list) [ ELSE (print-list) ]