Editing Data-Dictionary (section)

= Data Dictionary =

<blockquote>'''Document ID:''' PGCBL-DDD-001 · '''Version:''' 1.0 · '''Status:''' Approved · '''Last updated:''' 2026-03-17
</blockquote>
'''← [[Technical-Specification|Technical Specification]]''' | [[Flow-Diagrams|Flow Diagrams →]]


-----

<span id="contents"></span>
== Contents ==

# [[#conventions|Conventions]]
# [[#1-control-blocks-copybooks|Control Blocks — Copybooks]]
#* [[#11-primes-session|1.1 primes-session]]
#* [[#12-primes-dal|1.2 primes-dal]]
#* [[#13-primes-ui|1.3 primes-ui]]
#* [[#14-primes-table--sql-host-variable-character|1.4 primes-table (character)]]
#* [[#15-primes_table--sql-host-variable-packed|1.5 primes_table (packed)]]
#* [[#16-sqlca--sql-communications-area|1.6 SQLCA]]
# [[#2-working-storage-variables|Working-Storage Variables]]
#* [[#21-primesmain|2.1 primesmain]]
#* [[#22-primesgen|2.2 primesgen]]
#* [[#23-primes-dal|2.3 primes (DAL)]]
#* [[#24-primesui|2.4 primesui]]
# [[#3-database-objects|Database Objects]]
#* [[#31-schema-primes|3.1 Schema primes]]
#* [[#32-table-primesprimes|3.2 Table primes.primes]]
#* [[#33-sequence-asc_ident|3.3 Sequence asc_ident]]
#* [[#34-cursor-primescursor-runtime|3.4 Cursor primescursor]]


-----

<span id="conventions"></span>
== Conventions ==

{|
!width="50%"| Symbol
!width="50%"| Meaning
|-
| <code>PIC X(n)</code>
| Alphanumeric, n characters
|-
| <code>PIC 9(n)</code>
| Unsigned packed decimal display, n digits
|-
| <code>PIC S9(n)</code>
| Signed packed decimal display, n digits
|-
| <code>PIC 9(n)V9(m)</code>
| Unsigned numeric with m implied decimal places (no decimal point stored)
|-
| <code>PIC Z(n)</code>
| Zero-suppressed display numeric, n digits
|-
| <code>COMP-3</code>
| Packed-decimal binary storage (2 digits per byte + sign nibble)
|-
| <code>COMP-5</code>
| Native binary integer (platform word size)
|-
| <code>88</code>
| Condition-name — a boolean alias tested via <code>IF &lt;name&gt;</code> or <code>WHEN &lt;name&gt;</code>
|-
| <code>—</code>
| Not applicable (group item or 88-level)
|-
| ⚠️
| Known issue or deviation from standard
|}

'''Level hierarchy used in this codebase:'''

<pre>01  Group root
 03  Sub-group or elementary item
  05  Nested elementary item
   07  Doubly-nested elementary item
   49  Special level for variable-length groups (SQLERRM in SQLCA)
88  Condition-name (under any level)</pre>

-----

<span id="control-blocks-copybooks"></span>
== 1. Control Blocks — Copybooks ==

<span id="primes-session"></span>
=== 1.1 primes-session ===

<blockquote>'''Source file:''' <code>primes-session.cpy</code><br />
'''Included by:''' <code>primesmain.cbl</code> (WORKING-STORAGE) · <code>primesgen.cbl</code> (LINKAGE SECTION)<br />
'''Purpose:''' Session-tier control block. primesmain sets <code>methods</code>; primesgen reads it and sets <code>session-result</code>.
</blockquote>
{|
!width="16%"| Level
!width="16%"| Name
!width="16%"| PIC
!width="16%"| Usage
!width="16%"| Initial
!width="16%"| Description
|-
| 01
| <code>primes-session</code>
| —
| —
| —
| Root of session control block
|-
| 03
| <code>methods</code>
| <code>X(32)</code>
| DISPLAY
| —
| Method dispatch verb — set by primesmain before calling primesgen
|-
| 88
| <code>report-primes</code>
| —
| —
| <code>&quot;report&quot;</code>
| Run the cursor report path
|-
| 88
| <code>generate-primes</code>
| —
| —
| <code>&quot;generate&quot;</code>
| Run the sieve generation path
|-
| 88
| <code>start-primes</code>
| —
| —
| <code>&quot;start&quot;</code>
| Reserved — not used in current flow
|-
| 88
| <code>stop-primes</code>
| —
| —
| <code>&quot;stop&quot;</code>
| Reserved — not used in current flow
|-
| 88
| <code>invalid-method</code>
| —
| —
| <code>&quot;bad&quot;</code>
| Sentinel for unrecognised verb
|-
| 03
| <code>session-result</code>
| <code>9(2)</code>
| DISPLAY
| 0
| Outcome code written by primesgen
|-
| 88
| <code>session-method-ok</code>
| —
| —
| 0
| Operation succeeded
|-
| 88
| <code>session-method-nok</code>
| —
| —
| 1
| Operation failed
|-
| 88
| <code>session-method-eof</code>
| —
| —
| 9
| End of data (cursor exhausted)
|}

<blockquote>⚠️ <code>session-method-eof</code> (value 9) is never explicitly set in the current code. Fetch failure sets <code>session-result = 1</code> (nok), not 9. See [[Technical-Specification#7-known-technical-issues|Technical Specification — Defect T7]].
</blockquote>

-----

<span id="primes-dal"></span>
=== 1.2 primes-dal ===

<blockquote>'''Source file:''' <code>primes-dal.cpy</code><br />
'''Included by:''' <code>primesgen.cbl</code> (WORKING-STORAGE, caller) · <code>primes.cbl</code> (LINKAGE SECTION, callee)<br />
'''Purpose:''' DAL-tier control block. primesgen sets <code>dal-methods</code> and reads back <code>dal-result</code> and <code>primes-data</code>.
</blockquote>
{|
!width="16%"| Level
!width="16%"| Name
!width="16%"| PIC
!width="16%"| Usage
!width="16%"| Initial
!width="16%"| Description
|-
| 01
| <code>primes-dal</code>
| —
| —
| —
| Root of DAL control block
|-
| 03
| <code>dal-methods</code>
| <code>X(32)</code>
| DISPLAY
| —
| Method dispatch verb
|-
| 88
| <code>next-prime</code>
| —
| —
| <code>&quot;next-prime&quot;</code>
| Fetch next row from open cursor
|-
| 88
| <code>next-divider</code>
| —
| —
| <code>&quot;next-divider&quot;</code>
| SELECT a prime by ident for use as trial divisor
|-
| 88
| <code>write-prime</code>
| —
| —
| <code>&quot;write&quot;</code>
| INSERT a confirmed prime into the table
|-
| 88
| <code>db-cursor</code>
| —
| —
| <code>&quot;cursor&quot;</code>
| START TRANSACTION and OPEN primescursor
|-
| 88
| <code>db-connect</code>
| —
| —
| <code>&quot;connect&quot;</code>
| Establish the PostgreSQL connection
|-
| 88
| <code>db-disconnect</code>
| —
| —
| <code>&quot;disconnect&quot;</code>
| Release the connection
|-
| 88
| <code>invalid-method</code>
| —
| —
| <code>&quot;bad&quot;</code>
| Sentinel for unrecognised verb
|-
| 03
| <code>primes-data</code>
| —
| —
| —
| Single-row data payload (one prime)
|-
| 05
| <code>primes-sequence</code>
| <code>9(9)</code>
| DISPLAY
| —
| Row identity (<code>ident</code>) of the fetched prime
|-
| 05
| <code>prime-number</code>
| <code>9(9)</code>
| DISPLAY
| —
| The prime value itself
|-
| 03
| <code>dal-result</code>
| <code>9(2)</code>
| DISPLAY
| 0
| Outcome code written by primes
|-
| 88
| <code>dal-method-ok</code>
| —
| —
| 0
| Operation succeeded
|-
| 88
| <code>dal-method-nok</code>
| —
| —
| 1
| Operation failed
|-
| 88
| <code>dal-method-eof</code>
| —
| —
| 99
| Cursor exhausted (no more rows)
|}


-----

<span id="primes-ui"></span>
=== 1.3 primes-ui ===

<blockquote>'''Source file:''' <code>primes-ui.cpy</code><br />
'''Included by:''' all four programs<br />
'''Purpose:''' UI-tier control block. Any program sets <code>ui-methods</code> and <code>process-message</code> / <code>u-primes</code>, then calls primesui; primesui sets <code>ui-method-result</code>.
</blockquote>
{|
!width="16%"| Level
!width="16%"| Name
!width="16%"| PIC
!width="16%"| Usage
!width="16%"| Initial
!width="16%"| Description
|-
| 01
| <code>primes-ui</code>
| —
| —
| —
| Root of UI control block
|-
| 03
| <code>ui-methods</code>
| <code>X(32)</code>
| DISPLAY
| —
| Method dispatch verb
|-
| 88
| <code>write-ui</code>
| —
| —
| <code>&quot;write&quot;</code>
| Add one prime row to the print buffer
|-
| 88
| <code>message-ui</code>
| —
| —
| <code>&quot;log-message&quot;</code>
| Write <code>process-message</code> to the console
|-
| 88
| <code>start-ui</code>
| —
| —
| <code>&quot;start&quot;</code>
| Open <code>primes.prt</code>
|-
| 88
| <code>stop-ui</code>
| —
| —
| <code>&quot;stop&quot;</code>
| Flush print buffer and close file
|-
| 03
| <code>process-message</code>
| —
| —
| —
| Structured 132-char console log record
|-
| 05
| <code>program-name</code>
| <code>X(20)</code>
| DISPLAY
| —
| Name of the calling program
|-
| 05
| <code>program-line</code>
| —
| —
| —
| Location within the calling program
|-
| 07
| <code>program-paragraph</code>
| <code>X(20)</code>
| DISPLAY
| —
| Name of the calling paragraph
|-
| 07
| <code>program-message</code>
| <code>X(92)</code>
| DISPLAY
| —
| Human-readable status or error text
|-
| 03
| <code>u-primes</code>
| —
| —
| —
| One prime row for the print writer
|-
| 05
| <code>u-sequence</code>
| <code>9(9)</code>
| DISPLAY
| —
| Sequence number (ident) to write to print buffer
|-
| 05
| <code>u-number</code>
| <code>9(9)</code>
| DISPLAY
| —
| Prime value to write to print buffer
|-
| 03
| <code>ui-method-result</code>
| <code>9(2)</code>
| DISPLAY
| 0
| Outcome code written by primesui
|-
| 88
| <code>ui-method-ok</code>
| —
| —
| 0
| Operation succeeded
|-
| 88
| <code>ui-method-nok</code>
| —
| —
| 1
| Operation failed
|}

'''Console message layout''' (132 characters, left-to-right):

<pre>┌──────────────────────┬──────────────────────┬────────────────────────────────────────────────────────────────────────────────────────────┐
│  program-name (20)   │ program-paragraph(20)│  program-message (92)                                                                      │
└──────────────────────┴──────────────────────┴────────────────────────────────────────────────────────────────────────────────────────────┘</pre>

-----

<span id="primes-table-sql-host-variable-character"></span>
=== 1.4 primes-table — SQL Host Variable (character) ===

<blockquote>'''Source file:''' <code>primes-table.cpy</code><br />
'''Included by:''' <code>primes.cbl</code> via <code>EXEC SQL INCLUDE primes-table END-EXEC</code><br />
'''Purpose:''' Host variable layout for GixSQL to bind the <code>primes.primes</code> table columns.
</blockquote>
{|
!width="20%"| Level
!width="20%"| Name
!width="20%"| PIC
!width="20%"| Usage
!width="20%"| Description
|-
| 01
| <code>primes-table</code>
| —
| —
| Host variable group (character format)
|-
| 03
| <code>ident</code>
| <code>S9(9)</code>
| DISPLAY
| Maps to <code>primes.ident</code>; signed for SQL compatibility
|-
| 03
| <code>prime</code>
| <code>S9(9)</code>
| DISPLAY
| Maps to <code>primes.prime</code>; signed for SQL compatibility
|}


-----

<span id="primes_table-sql-host-variable-packed"></span>
=== 1.5 primes_table — SQL Host Variable (packed) ===

<blockquote>'''Source file:''' <code>primes_table.cpy</code><br />
'''Included by:''' <code>primes.cbl</code> (alternative layout)<br />
'''Purpose:''' COMP-3 variant of <code>primes-table</code>. The underscore in both the filename and root name is a deviation from the project’s hyphen convention.
</blockquote>
{|
! Level
! Name
! PIC
! Usage
! Description
|-
| 01
| <code>primes_table</code>
| —
| —
| Host variable group (COMP-3 format)
|-
| 03
| <code>ident</code>
| <code>S9(9)</code>
| COMP-3
| Row identity — packed decimal
|-
| 03
| <code>prime</code>
| <code>S9(9)</code>
| COMP-3
| Prime value — packed decimal
|}

<blockquote>⚠️ Two nearly identical copybooks exist. <code>primes-table.cpy</code> (hyphens, DISPLAY) is used by the cursor FETCH target (<code>primes-row</code>). The canonical version should be designated and the other retired. See [[Technical-Specification#7-known-technical-issues|Technical Specification — Defect T6]].
</blockquote>

-----

<span id="sqlca-sql-communications-area"></span>
=== 1.6 SQLCA — SQL Communications Area ===

<blockquote>'''Source file:''' <code>SQLCA.cpy</code><br />
'''Included by:''' <code>primes.cbl</code> via <code>EXEC SQL INCLUDE SQLCA END-EXEC</code><br />
'''Purpose:''' Standard GixSQL communications area. Updated after every SQL statement.
</blockquote>
{|
!width="20%"| Level
!width="20%"| Name
!width="20%"| PIC
!width="20%"| Usage
!width="20%"| Description
|-
| 01
| <code>SQLCA</code>
| —
| —
| SQL communications area
|-
| 05
| <code>SQLCAID</code>
| <code>X(8)</code>
| DISPLAY
| SQLCA identifier string
|-
| 05
| <code>SQLCABC</code>
| <code>S9(9)</code>
| COMP-5
| Byte length of SQLCA structure
|-
| 05
| <code>SQLCODE</code>
| <code>S9(9)</code>
| COMP-5
| '''SQL return code:''' 0=success · negative=error · +100=not found
|-
| 05
| <code>SQLERRM</code>
| —
| —
| Error message group
|-
| 49
| <code>SQLERRML</code>
| <code>S9(4)</code>
| COMP-5
| Length of error message text
|-
| 49
| <code>SQLERRMC</code>
| <code>X(70)</code>
| DISPLAY
| Error message text from the database engine
|-
| 05
| <code>SQLERRP</code>
| <code>X(8)</code>
| DISPLAY
| Error procedure name (not used in this application)
|-
| 05
| <code>SQLERRD</code>
| <code>S9(9)</code> OCCURS 6
| COMP-5
| Diagnostic array; <code>SQLERRD(3)</code> = number of rows processed
|-
| 05
| <code>SQLWARN</code>
| —
| —
| Warning flags group (not used in this application)
|-
| 05
| <code>SQLSTATE</code>
| <code>X(5)</code>
| DISPLAY
| ISO/ANSI SQL state code (5-char string)
|}

'''SQLCODE reference (PostgreSQL / GixSQL):'''

{|
! Value
! Meaning
|-
| 0
| Statement succeeded
|-
| +100
| No rows found (SELECT returned empty, cursor exhausted)
|-
| negative
| Database error — see <code>SQLERRMC</code> for description
|}


-----

<span id="working-storage-variables"></span>
== 2. Working-Storage Variables ==

<span id="primesmain"></span>
=== 2.1 primesmain ===

<blockquote>'''Source:''' <code>primesmain.cbl</code> WORKING-STORAGE SECTION<br />
'''Copybooks included:''' <code>primes-session</code> · <code>primes-ui</code>
</blockquote>
{|
!width="20%"| Name
!width="20%"| PIC
!width="20%"| Usage
!width="20%"| Initial
!width="20%"| Description
|-
| <code>filler</code>
| <code>X(32)</code>
| DISPLAY
| <code>&quot;Start WS primesmain&quot;</code>
| Debug marker — locates WS start in memory dumps
|-
| <code>commandline-args</code>
| <code>X(32)</code>
| DISPLAY
| —
| Command-line argument from <code>ACCEPT … FROM COMMAND-LINE</code>
|-
| <code>execute-generate</code> (88)
| —
| —
| <code>&quot;generate&quot;</code>
| True when commandline-args = “generate”
|-
| <code>execute-report</code> (88)
| —
| —
| <code>&quot;report&quot;</code>
| True when commandline-args = “report”
|-
| <code>primes-session</code>
| (group)
| —
| —
| COPY primes-session — see [[#11-primes-session|§1.1]]
|-
| <code>primes-ui</code>
| (group)
| —
| —
| COPY primes-ui — see [[#13-primes-ui|§1.3]]
|}


-----

<span id="primesgen"></span>
=== 2.2 primesgen ===

<blockquote>'''Source:''' <code>primesgen.cbl</code> WORKING-STORAGE SECTION<br />
'''Copybooks included:''' <code>primes-ui</code> (WS) · <code>primes-dal</code> (WS) · <code>primes-session</code> (LINKAGE)
</blockquote>
'''Print control group (unused — print handled by primesui):'''

{|
!width="25%"| Name
!width="25%"| PIC
!width="25%"| Initial
!width="25%"| Description
|-
| <code>file-buffer</code>
| <code>X(132)</code>
| —
| FD record area for fprinter — declared but file never opened here ⚠️
|-
| <code>print-buffer</code>
| <code>X(132)</code>
| —
| Working print line buffer
|-
| <code>line-number</code>
| <code>99</code>
| 99
| Current line within page
|-
| <code>page-number</code>
| <code>9999</code>
| 0
| Current page number
|}

'''Sieve control group (01 <code>primes</code>, local to primesgen):'''

{|
!width="25%"| Name
!width="25%"| PIC
!width="25%"| Initial
!width="25%"| Description
|-
| <code>gen-methods</code>
| <code>X(32)</code>
| —
| Verb for the local <code>primes</code> group calls to primes.cbl
|-
| <code>query-process</code> (88)
| —
| <code>&quot;query&quot;</code>
| Internal: query
|-
| <code>start-process</code> (88)
| —
| <code>&quot;start&quot;</code>
| Internal: start
|-
| <code>next-divider</code> (88)
| —
| <code>&quot;get&quot;</code>
| Internal: fetch next divider
|-
| <code>write-prime</code> (88)
| —
| <code>&quot;put&quot;</code>
| Internal: write prime
|-
| <code>stop-process</code> (88)
| —
| <code>&quot;stop&quot;</code>
| Internal: stop
|-
| <code>primes-result</code>
| <code>9(2)</code>
| 0
| Internal result code for local DAL calls
|-
| <code>init-primes-ok</code> (88)
| —
| 1
| Initialisation succeeded
|-
| <code>first-divider-ok</code> (88)
| —
| 2
| First divisor retrieved
|-
| <code>next-divider-ok</code> (88)
| —
| 3
| Next divisor retrieved
|-
| <code>test-number</code>
| <code>9(9)</code>
| —
| '''Current candidate being tested for primality'''
|-
| <code>test-number-sqr</code>
| <code>9(9)V9(9)</code>
| —
| Square root of <code>test-number</code> — upper bound for divisors
|-
| <code>test-divider</code>
| <code>9(9)</code>
| —
| Current trial divisor (prime fetched from DB)
|-
| <code>test-rest</code>
| <code>9(9)V9(9)</code>
| —
| Remainder: <code>test-number MOD test-divider</code>
|-
| <code>old-test-number</code>
| <code>9(9)</code>
| —
| Previous candidate — diagnostic use only, not active
|-
| <code>old-ident</code>
| <code>9(9)</code>
| —
| DB <code>ident</code> of the most recently fetched divisor
|-
| <code>new-ident</code>
| <code>9(9)</code>
| —
| <code>old-ident + 1</code> — used as key for the next divider SELECT
|}

'''Other:'''

{|
!width="25%"| Name
!width="25%"| PIC
!width="25%"| Initial
!width="25%"| Description
|-
| <code>test-quot</code>
| <code>9(9)</code>
| —
| Integer quotient from <code>DIVIDE test-number BY test-divider</code>
|}


-----

<span id="primes-dal-1"></span>
=== 2.3 primes (DAL) ===

<blockquote>'''Source:''' <code>primes.cbl</code> WORKING-STORAGE SECTION<br />
'''Copybooks included:''' <code>primes-ui</code> (WS) · <code>SQLCA</code> (via EXEC SQL INCLUDE) · <code>primes-table</code> (via EXEC SQL INCLUDE) · <code>primes-dal</code> (LINKAGE)
</blockquote>
'''Database credentials:'''

{|
!width="25%"| Name
!width="25%"| PIC
!width="25%"| Initial
!width="25%"| Description
|-
| <code>DATASRC</code>
| <code>X(64)</code>
| <code>&quot;pgsql://localhost:5432/primes&amp;default_schema=primes&quot;</code>
| GixSQL connection string ⚠️ hard-coded
|-
| <code>DBUSR</code>
| <code>X(64)</code>
| <code>&quot;primes_user&quot;</code>
| Database user name ⚠️ hard-coded
|-
| <code>DBPWD</code>
| <code>X(64)</code>
| <code>&quot;pr1mes_user&quot;</code>
| Database password ⚠️ hard-coded in plain text
|-
| <code>CUR-STEP</code>
| <code>X(16)</code>
| —
| Diagnostic step label (<code>&quot;CONNECT&quot;</code> / <code>&quot;DISCONNECT&quot;</code>)
|}

'''Cursor fetch buffer:'''

{|
!width="25%"| Name
!width="25%"| PIC
!width="25%"| Usage
!width="25%"| Description
|-
| <code>primes-row</code>
| (group)
| —
| Target group for <code>FETCH primescursor INTO :primes-row</code>
|-
| <code>r-ident</code>
| <code>9(9)</code>
| COMP-3
| Fetched row identity value
|-
| <code>r-prime</code>
| <code>9(9)</code>
| COMP-3
| Fetched prime value
|}

'''Unused declarations:'''

{|
! Name
! PIC
! Note
|-
| <code>prime-count</code>
| <code>9(9)</code>
| Declared; not written to in current flow
|-
| <code>prime_seq</code>
| <code>9(9)</code>
| Declared; not written to
|-
| <code>divider</code>
| <code>9(9)</code>
| Declared; not written to
|}

'''Local sieve control group (01 <code>primes</code>, mirrors primesgen layout):'''

Mirrors the <code>01 primes</code> group in primesgen. Contains <code>test-divider</code>, <code>old-ident</code>, <code>new-ident</code> etc., used internally by <code>r81-get-next-divider</code>. See [[#22-primesgen|§2.2]] for field descriptions.


-----

<span id="primesui"></span>
=== 2.4 primesui ===

<blockquote>'''Source:''' <code>primesui.cbl</code> WORKING-STORAGE SECTION<br />
'''Copybooks included:''' <code>primes-ui</code> (LINKAGE)
</blockquote>
'''Print row buffer:'''

{|
!width="20%"| Name
!width="20%"| PIC
!width="20%"| Usage
!width="20%"| Initial
!width="20%"| Description
|-
| <code>primes-table</code> (01)
| —
| —
| —
| 6-element row accumulator
|-
| <code>primes-cel</code>
| OCCURS 6 INDEXED <code>primes-idx</code>
| —
| —
| One cell = one prime entry in the output line
|-
| <code>t-ident</code>
| <code>Z(9)</code>
| DISPLAY
| —
| Zero-suppressed sequence number for this cell
|-
| filler
| <code>X(2)</code>
| DISPLAY
| spaces
| Column separator
|-
| <code>t-prime</code>
| <code>Z(9)</code>
| DISPLAY
| —
| Zero-suppressed prime value for this cell
|-
| filler
| <code>X(2)</code>
| DISPLAY
| spaces
| Column separator
|-
| <code>primes-idx</code>
| INDEX
| —
| —
| Current cell position (1–6); set by <code>SET primes-idx</code>
|}

'''Column header:'''

{|
!width="33%"| Name
!width="33%"| PIC
!width="33%"| Description
|-
| <code>table-header</code> (01)
| OCCURS 6
| Static header row — <code>&quot;Sequence  Prime  &quot;</code> repeated 6 times
|}

'''Print control:'''

{|
!width="20%"| Name
!width="20%"| PIC
!width="20%"| Usage
!width="20%"| Initial
!width="20%"| Description
|-
| <code>print-buffer</code>
| <code>X(132)</code>
| DISPLAY
| —
| Working buffer written to <code>fprinter</code>
|-
| <code>primes-prt-status</code>
| <code>X(2)</code>
| DISPLAY
| —
| File status from last <code>fprinter</code> operation
|-
| <code>page-number</code>
| <code>9(4)</code>
| DISPLAY
| 1
| Current page number
|-
| <code>print-new-page</code>
| <code>9</code>
| DISPLAY
| 1
| New-page flag — 1 = heading must be written
|-
| <code>new-page</code> (88)
| —
| —
| 1
| True when <code>print-new-page = 1</code>
|}

'''Static strings:'''

{|
!width="25%"| Name
!width="25%"| PIC
!width="25%"| Value
!width="25%"| Description
|-
| <code>primes-heading</code>
| <code>X(118)</code>
| <code>&quot;primes overview&quot;</code>
| Left-justified page heading text
|-
| <code>primes-footing</code>
| (group)
| —
| Page footer group
|-
| filler
| <code>X(118)</code>
| SPACE
| Left padding of footer
|-
| filler
| <code>X(6)</code>
| <code>&quot;page: &quot;</code>
| Footer label
|-
| <code>f-page-number</code>
| <code>Z(3)9</code>
| 1
| Formatted page number (zero-suppressed 4-digit)
|}

'''Unused:'''

{|
! Name
! PIC
! Note
|-
| <code>primes-line</code>
| <code>X(132)</code>
| Declared; not written to in current flow
|-
| <code>primes-count</code>
| <code>9(8)</code>
| Declared; not used
|}


-----

<span id="database-objects"></span>
== 3. Database Objects ==

<span id="schema-primes"></span>
=== 3.1 Schema <code>primes</code> ===

{|
!width="25%"| Object
!width="25%"| Type
!width="25%"| Owner
!width="25%"| Description
|-
| <code>primes</code>
| SCHEMA
| <code>primes_user</code>
| Container schema for all application objects
|-
| <code>asc_ident</code>
| SEQUENCE
| <code>primes_user</code>
| Auto-incrementing identity for <code>primes.ident</code>
|-
| <code>primes.primes</code>
| TABLE
| <code>primes_user</code>
| The prime numbers store
|}


-----

<span id="table-primes.primes"></span>
=== 3.2 Table <code>primes.primes</code> ===

<blockquote>'''DDL source:''' <code>primes_schema.sql</code>
</blockquote>
<syntaxhighlight lang="sql">CREATE TABLE primes.primes (
    ident integer DEFAULT nextval('primes.asc_ident'::regclass),
    prime integer
);</syntaxhighlight>
{|
!width="20%"| Column
!width="20%"| Data type
!width="20%"| Nullable
!width="20%"| Default
!width="20%"| Description
|-
| <code>ident</code>
| INTEGER
| YES
| <code>nextval('primes.asc_ident')</code>
| Auto-assigned insertion sequence; acts as primary key but has no formal PK constraint
|-
| <code>prime</code>
| INTEGER
| YES
| —
| The prime number value
|}

<blockquote>⚠️ No PRIMARY KEY, UNIQUE constraint, or index is defined on either column. The <code>ident</code> column is the key used by <code>r81-get-next-divider</code> (<code>SELECT prime WHERE ident = :new-ident</code>). Without an index, this is a sequential scan. See [[Technical-Specification#7-known-technical-issues|Technical Specification — Defect T5]] (performance concern).
</blockquote>

-----

<span id="sequence-primes.asc_ident"></span>
=== 3.3 Sequence <code>primes.asc_ident</code> ===

{|
! Attribute
! Value
|-
| Data type
| INTEGER
|-
| Start value
| 1
|-
| Increment
| 1
|-
| Minimum
| 1 (default)
|-
| Maximum
| 2,147,483,647 (INTEGER max)
|-
| Cache
| 1
|-
| Cycle
| No
|}


-----

<span id="cursor-primescursor-runtime"></span>
=== 3.4 Cursor <code>primescursor</code> (runtime) ===

<blockquote>Declared at compile time in <code>primes.cbl</code>. Opened and used only in the '''report path'''.
</blockquote>
{|
!width="50%"| Attribute
!width="50%"| Value
|-
| Declaration
| <code>DECLARE primescursor CURSOR FOR SELECT * FROM primes</code>
|-
| Connection alias
| <code>primes</code>
|-
| Declared at
| Compile time in <code>primes.cbl</code>
|-
| Transaction
| Opened inside <code>START TRANSACTION</code> in <code>s01-cursor</code>
|-
| Opened at
| <code>s01-cursor</code> paragraph (<code>EXEC SQL OPEN primescursor</code>)
|-
| Fetch target
| <code>primes-row</code> group (<code>r-ident</code>, <code>r-prime</code>) — COMP-3 fields
|-
| Close
| Not explicit; closed implicitly when <code>CONNECT RESET primes</code> is issued
|}

<blockquote>⚠️ <code>SELECT * FROM primes</code> is used. Best practice is to name columns explicitly (<code>SELECT ident, prime FROM primes</code>) to guard against schema changes. The pre-compiler listing (<code>primes_cbsql.out</code>) shows this was expanded from a <code>SELECT ident, prime</code> form in an earlier version.
</blockquote>

-----

'''← [[Technical-Specification|Technical Specification]]''' | [[Flow-Diagrams|Flow Diagrams →]]