diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/catalog/pg_attribute.h | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/src/backend/catalog/pg_attribute.h b/src/backend/catalog/pg_attribute.h index 0888ee2d7ff..ab2d625f3ef 100644 --- a/src/backend/catalog/pg_attribute.h +++ b/src/backend/catalog/pg_attribute.h @@ -7,7 +7,7 @@ * * Copyright (c) 1994, Regents of the University of California * - * $Id: pg_attribute.h,v 1.1.1.1.2.1 1996/08/21 04:23:32 scrappy Exp $ + * $Id: pg_attribute.h,v 1.1.1.1.2.2 1996/08/24 20:56:42 scrappy Exp $ * * NOTES * the genbki.sh script reads this file and generates .bki @@ -44,13 +44,19 @@ CATALOG(pg_attribute) BOOTSTRAP { Oid attrelid; NameData attname; Oid atttypid; + /* atttypid is the OID of the instance in Catalog Class pg_type that + defines the data type of this attribute (e.g. int4). Information in + that instance is redundant with the attlen, attbyval, and attalign + attributes of this instance, so they had better match or Postgres + will fail. + */ Oid attdefrel; int4 attnvals; Oid atttyparg; /* type arg for arrays/spquel/procs */ int2 attlen; - /* attlen is the number of bytes we use to represent the value - of this attribute, e.g. 4 for an int4. But for a variable length - attribute, attlen is -1. + /* attlen is a copy of the typlen field from pg_type for this + attribute. See atttypid above. See struct TypeTupleFormData for + definition. */ int2 attnum; /* attnum is the "attribute number" for the attribute: A @@ -68,6 +74,10 @@ CATALOG(pg_attribute) BOOTSTRAP { */ int2 attbound; bool attbyval; + /* attbyval is a copy of the typbyval field from pg_type for this + attribute. See atttypid above. See struct TypeTupleFormData for + definition. + */ bool attcanindex; Oid attproc; /* spquel? */ int4 attnelems; @@ -80,7 +90,11 @@ CATALOG(pg_attribute) BOOTSTRAP { walking process. */ bool attisset; - char attalign; /* alignment (c=char, s=short, i=int, d=double) */ + char attalign; + /* attalign is a copy of the typalign field from pg_type for this + attribute. See atttypid above. See struct TypeTupleFormData for + definition. + */ } FormData_pg_attribute; /* |