Compaq COBOL AAQ2G1FTK, Руководство пользователя

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Image activation optimization, 15–25
/INCLUDE, 1–33
-include flag, 1–12
Index data item, 4–16
declaration, 4–16
modifying with SET, 4–16
where defined, 4–3
Indexed file
See also Optimization
access modes, 6–34
alternate key, 6–7
and ISAM mapping, 6–47
AT END condition, 7–2
capabilities, 6–6
creating, 6–32
creating and populating, 6–33
defining, 6–22
design considerations, 6–13
I/O statements, 6–33
index, 6–7
invalid key condition, 7–2
INVALID KEY condition, 7–2
key, 6–7
duplicate, 6–7
length, 6–7
location, 6–7
number of key data items
compiler implementation specifications,
A–1
open modes, 6–34
optional key, 6–7
organization, 6–6
advantages, 6–3
disadvantages, 6–3
specifying, 6–21
organization (fig.), 6–7
populating, 6–32
primary key, 6–7
processing, 6–33
reading, 6–42
dynamically, 6–44
example, 6–46
with READ PRIOR, 6–47
randomly, 6–43
example, 6–44
sequentially, 6–42
example, 6–43
reading from other language, 6–47
reorganizing, 6–33
SELECT statements, 6–24
specifying file organization and access mode,
6–22
updating, 6–55
random access mode, 6–55
sequential access mode, 6–55
updating records
dynamically, 6–59
randomly, 6–57
Indexed file
updating records
randomly (cont’d)
example, 6–59
sequentially, 6–56
example, 6–57
valid I/O statements (tab.), 6–34
writing, 6–34
Indexes, 4–1
initializing, 4–15
Indexing
advantages, 15–9
efficiency order, 15–9
Indexing compared with subscripting, 15–9
Index name
subscript value
compiler implementation specifications,
A–3
INITIAL clause
use of, 12–4
Initializing
tables, 4–10 to 4–12
INPUT and OUTPUT PROCEDURE phrases
example, 9–4
Inspecting data
active/inactive arguments, 5–22
BEFORE/AFTER, 5–18
finding a match, 5–23
implicit redefinition, 5–18
INSPECT operation, 5–21
interference in tally argument list, 5–27
REPLACING, 5–30
scanner setting, 5–22
tally argument, 5–24
tally counter, 5–24
TALLYING phrase, 5–24
INSPECT statement, 5–17 to 5–33
AFTER, 5–18
BEFORE, 5–18
common errors, 5–33
CONVERTING, 5–33
function, 5–17
how the INSPECT statement inspects data,
5–21
implicit redefinition, 5–18
values resulting from (tab.), 5–19
relationship among INSPECT argument,
delimiter, item value, and argument active
position (tab.), 5–22
REPLACING option, 5–17
REPLACING phrase
interference in the replacement argument
list, 5–32
replacement argument, 5–31
replacement argument (fig.), 5–31
replacement argument list, 5–31
replacement value, 5–31
sample (fig.), 5–21
Index–13