In expanded mode psql calculates the width of the longest field in all the
output rows,
and prints the header line according to it. This often results in record header
wrapping
over several lines (see example below).
This huge record header is printed the same way before each record, even if all
the fields
in current record are small and fit into terminal width. This often leads to
situations
when record header occupies the entirety of the screen, for all records, even
though there are
only a few records with huge fields in a record set.
Maybe we can avoid making the header line longer than terminal width for \pset
border 0
and \pset border 1? We already have terminal width calculated. Please see
attached a patch
with the proposed implementation.
Example output before the modification, in a terminal with a 100-column width:
$ psql template1 -c "\x on" -c "\pset border 1;" -c "select n, repeat('x', n) as
long_column_name from unnest(array[42,210]) as n"
Expanded display is on.
Border style is 1.
─[ RECORD 1
]────┬──────────────────────────────────────────────────────────────────────────────────
────────────────────────────────────────────────────────────────────────────────────────────────────
─────────────────────────────
n │ 42
long_column_name │ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
─[ RECORD 2
]────┼──────────────────────────────────────────────────────────────────────────────────
────────────────────────────────────────────────────────────────────────────────────────────────────
─────────────────────────────
n │ 210
long_column_name │
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
And here's the same command after the patch:
$ psql template1 -c "\x on" -c "\pset border 1;" -c "select n, repeat('x', n) as
long_column_name from unnest(array[42,210]) as n"
Expanded display is on.
Border style is 1.
─[ RECORD 1
]────┬──────────────────────────────────────────────────────────────────────────────────
n │ 42
long_column_name │ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
─[ RECORD 2
]────┼──────────────────────────────────────────────────────────────────────────────────
n │ 210
long_column_name │
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Best regards,
Platon Pronko
diff --git a/src/fe_utils/print.c b/src/fe_utils/print.c
index d48fcc4a03..9483d0d852 100644
--- a/src/fe_utils/print.c
+++ b/src/fe_utils/print.c
@@ -1157,6 +1157,7 @@ print_aligned_vertical_line(const printTextFormat *format,
unsigned long record,
unsigned int hwidth,
unsigned int dwidth,
+ int output_columns,
printTextRule pos,
FILE *fout)
{
@@ -1200,6 +1201,14 @@ print_aligned_vertical_line(const printTextFormat *format,
}
if (reclen < 0)
reclen = 0;
+
+ if (output_columns > 0) {
+ if (opt_border == 0)
+ dwidth = Min(dwidth, output_columns - hwidth);
+ if (opt_border == 1)
+ dwidth = Min(dwidth, output_columns - hwidth - 3);
+ }
+
for (i = reclen; i < dwidth; i++)
fputs(opt_border > 0 ? lformat->hrule : " ", fout);
if (opt_border == 2)
@@ -1501,10 +1510,11 @@ print_aligned_vertical(const printTableContent *cont,
if (!opt_tuples_only)
print_aligned_vertical_line(format, opt_border, record++,
- lhwidth, dwidth, pos, fout);
+ lhwidth, dwidth, output_columns,
+ pos, fout);
else if (i != 0 || !cont->opt->start_table || opt_border == 2)
print_aligned_vertical_line(format, opt_border, 0, lhwidth,
- dwidth, pos, fout);
+ dwidth, output_columns, pos, fout);
}
/* Format the header */
@@ -1691,7 +1701,7 @@ print_aligned_vertical(const printTableContent *cont,
{
if (opt_border == 2 && !cancel_pressed)
print_aligned_vertical_line(format, opt_border, 0, hwidth, dwidth,
- PRINT_RULE_BOTTOM, fout);
+ output_columns, PRINT_RULE_BOTTOM, fout);
/* print footers */
if (!opt_tuples_only && cont->footers != NULL && !cancel_pressed)
