Rethink \crosstabview's argument parsing logic.

\crosstabview interpreted its arguments in an unusual way, including
doing case-insensitive matching of unquoted column names, which is
surely not the right thing.  Rip that out in favor of doing something
equivalent to the dequoting/case-folding rules used by other psql
commands.  To keep it simple, change the syntax so that the optional
sort column is specified as a separate argument, instead of the
also-quite-unusual syntax that attached it to the colH argument with
a colon.

Also, rework the error messages to be closer to project style.

doc/src/sgml/ref/psql-ref.sgml

@@ -993,9 +993,10 @@ testdb=>
       <varlistentry id="APP-PSQL-meta-commands-crosstabview">
         <term><literal>\crosstabview [
             <replaceable class="parameter">colV</replaceable>
-            <replaceable class="parameter">colH</replaceable>[:<replaceable class="parameter">scolH</replaceable>]
-            [<replaceable class="parameter">colD</replaceable>]
-            ] </literal></term>
+            [ <replaceable class="parameter">colH</replaceable>
+            [ <replaceable class="parameter">colD</replaceable>
+            [ <replaceable class="parameter">sortcolH</replaceable>
+            ] ] ] ] </literal></term>
         <listitem>
         <para>
         Executes the current query buffer (like <literal>\g</literal>) and
@@ -1004,16 +1005,11 @@ testdb=&gt;
         The output column identified by <replaceable class="parameter">colV</>
         becomes a vertical header and the output column identified by
         <replaceable class="parameter">colH</replaceable>
-        becomes a horizontal header, optionally sorted by ranking data obtained
-        from column <replaceable class="parameter">scolH</replaceable>.
+        becomes a horizontal header.
         <replaceable class="parameter">colD</replaceable> identifies
         the output column to display within the grid.
-        If <replaceable class="parameter">colD</replaceable> is not
-        specified and there are exactly three columns in the result set,
-        the column that is neither
-        <replaceable class="parameter">colV</replaceable> nor
-        <replaceable class="parameter">colH</replaceable>
-        is displayed; if there are more columns, an error is reported.
+        <replaceable class="parameter">sortcolH</replaceable> identifies
+        an optional sort column for the horizontal header.
         </para>
 
         <para>
@@ -1024,6 +1020,12 @@ testdb=&gt;
         and <replaceable class="parameter">colH</replaceable> as column 2.
         <replaceable class="parameter">colH</replaceable> must differ from
         <replaceable class="parameter">colV</replaceable>.
+        If <replaceable class="parameter">colD</replaceable> is not
+        specified, then there must be exactly three columns in the query
+        result, and the column that is neither
+        <replaceable class="parameter">colV</replaceable> nor
+        <replaceable class="parameter">colH</replaceable>
+        is taken to be <replaceable class="parameter">colD</replaceable>.
         </para>
 
         <para>
@@ -1037,11 +1039,11 @@ testdb=&gt;
         found in column <replaceable class="parameter">colH</replaceable>,
         with duplicates removed.  By default, these appear in the same order
         as in the query results.  But if the
-        optional <replaceable class="parameter">scolH</> argument is given, it
-        identifies a column whose values must be integer numbers, and the
+        optional <replaceable class="parameter">sortcolH</> argument is given,
+        it identifies a column whose values must be integer numbers, and the
         values from <replaceable class="parameter">colH</replaceable> will
         appear in the horizontal header sorted according to the
-        corresponding <replaceable class="parameter">scolH</> values.
+        corresponding <replaceable class="parameter">sortcolH</> values.
         </para>
 
         <para>

src/bin/psql/command.c

@@ -368,13 +368,11 @@ exec_command(const char *cmd,
 	/* \crosstabview -- execute a query and display results in crosstab */
 	else if (strcmp(cmd, "crosstabview") == 0)
 	{
-		pset.ctv_col_V = psql_scan_slash_option(scan_state,
-												OT_NORMAL, NULL, false);
-		pset.ctv_col_H = psql_scan_slash_option(scan_state,
-												OT_NORMAL, NULL, false);
-		pset.ctv_col_D = psql_scan_slash_option(scan_state,
-												OT_NORMAL, NULL, false);
+		int			i;
 
+		for (i = 0; i < lengthof(pset.ctv_args); i++)
+			pset.ctv_args[i] = psql_scan_slash_option(scan_state,
+													  OT_NORMAL, NULL, true);
 		pset.crosstab_flag = true;
 		status = PSQL_CMD_SEND;
 	}

src/bin/psql/common.c

@@ -1130,6 +1130,7 @@ SendQuery(const char *query)
 	PGTransactionStatusType transaction_status;
 	double		elapsed_msec = 0;
 	bool		OK = false;
+	int			i;
 	bool		on_error_rollback_savepoint = false;
 	static bool on_error_rollback_warning = false;
 
@@ -1362,20 +1363,10 @@ sendquery_cleanup:
 
 	/* reset \crosstabview trigger */
 	pset.crosstab_flag = false;
-	if (pset.ctv_col_V)
-	{
-		free(pset.ctv_col_V);
-		pset.ctv_col_V = NULL;
-	}
-	if (pset.ctv_col_H)
-	{
-		free(pset.ctv_col_H);
-		pset.ctv_col_H = NULL;
-	}
-	if (pset.ctv_col_D)
+	for (i = 0; i < lengthof(pset.ctv_args); i++)
 	{
-		free(pset.ctv_col_D);
-		pset.ctv_col_D = NULL;
+		pg_free(pset.ctv_args[i]);
+		pset.ctv_args[i] = NULL;
 	}
 
 	return OK;

src/bin/psql/settings.h

@@ -94,9 +94,7 @@ typedef struct _psqlSettings
 	char	   *gset_prefix;	/* one-shot prefix argument for \gset */
 	bool		gexec_flag;		/* one-shot flag to execute query's results */
 	bool		crosstab_flag;	/* one-shot request to crosstab results */
-	char	   *ctv_col_V;		/* \crosstabview 1st argument */
-	char	   *ctv_col_H;		/* \crosstabview 2nd argument */
-	char	   *ctv_col_D;		/* \crosstabview 3nd argument */
+	char	   *ctv_args[4];	/* \crosstabview arguments */
 
 	bool		notty;			/* stdin or stdout is not a tty (as determined
 								 * on startup) */

src/test/regress/expected/psql_crosstab.out

@@ -35,7 +35,7 @@ SELECT v, EXTRACT(year FROM d), count(*)
 -- ordered months in horizontal header, quoted column name
 SELECT v, to_char(d, 'Mon') AS "month name", EXTRACT(month FROM d) AS num,
  count(*) FROM ctv_data  GROUP BY 1,2,3 ORDER BY 1
- \crosstabview v "month name":num 4
+ \crosstabview v "month name" 4 num
  v  | Jan | Apr | Jul | Dec 
 ----+-----+-----+-----+-----
  v0 |     |     |   2 |   1
@@ -50,7 +50,7 @@ SELECT EXTRACT(year FROM d) AS year, to_char(d,'Mon') AS "month name",
   FROM ctv_data
   GROUP BY EXTRACT(year FROM d), to_char(d,'Mon'), EXTRACT(month FROM d)
 ORDER BY month
-\crosstabview "month name" year:year format
+\crosstabview "month name" year format year
  month name |      2014       |      2015      
 ------------+-----------------+----------------
  Jan        |                 | sum=3 avg=3.0
@@ -74,7 +74,7 @@ SELECT v, h, string_agg(c, E'\n') FROM ctv_data GROUP BY v, h ORDER BY 1,2,3
 -- horizontal ASC order from window function
 SELECT v,h, string_agg(c, E'\n') AS c, row_number() OVER(ORDER BY h) AS r
 FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
- \crosstabview v h:r c
+ \crosstabview v h c r
  v  | h0  | h1  |  h2  | h4  |     
 ----+-----+-----+------+-----+-----
  v0 |     |     |      | qux+| qux
@@ -87,7 +87,7 @@ FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
 -- horizontal DESC order from window function
 SELECT v, h, string_agg(c, E'\n') AS c, row_number() OVER(ORDER BY h DESC) AS r
 FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
- \crosstabview v h:r c
+ \crosstabview v h c r
  v  |     | h4  |  h2  | h1  | h0  
 ----+-----+-----+------+-----+-----
  v0 | qux | qux+|      |     | 
@@ -100,7 +100,7 @@ FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
 -- horizontal ASC order from window function, NULLs pushed rightmost
 SELECT v,h, string_agg(c, E'\n') AS c, row_number() OVER(ORDER BY h NULLS LAST) AS r
 FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
- \crosstabview v h:r c
+ \crosstabview v h c r
  v  | h0  | h1  |  h2  | h4  |     
 ----+-----+-----+------+-----+-----
  v0 |     |     |      | qux+| qux
@@ -112,7 +112,7 @@ FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
 
 -- only null, no column name, 2 columns: error
 SELECT null,null \crosstabview
-The query must return at least two columns to be shown in crosstab
+\crosstabview: query must return at least three columns
 -- only null, no column name, 3 columns: works
 SELECT null,null,null \crosstabview
  ?column? |  
@@ -163,23 +163,39 @@ FROM ctv_data GROUP BY v, h ORDER BY h,v
     |     |     |      | dbl | 
 (3 rows)
 
+-- refer to columns by quoted names, check downcasing of unquoted name
+SELECT 1 as "22", 2 as b, 3 as "Foo"
+ \crosstabview "22" B "Foo"
+ 22 | 2 
+----+---
+  1 | 3
+(1 row)
+
 -- error: bad column name
 SELECT v,h,c,i FROM ctv_data
  \crosstabview v h j
-Invalid column name: j
+\crosstabview: column name not found: "j"
+-- error: need to quote name
+SELECT 1 as "22", 2 as b, 3 as "Foo"
+ \crosstabview 1 2 Foo
+\crosstabview: column name not found: "foo"
+-- error: need to not quote name
+SELECT 1 as "22", 2 as b, 3 as "Foo"
+ \crosstabview 1 "B" "Foo"
+\crosstabview: column name not found: "B"
 -- error: bad column number
 SELECT v,h,i,c FROM ctv_data
  \crosstabview 2 1 5
-Invalid column number: 5
+\crosstabview: invalid column number: "5"
 -- error: same H and V columns
 SELECT v,h,i,c FROM ctv_data
  \crosstabview 2 h 4
-The same column cannot be used for both vertical and horizontal headers
+\crosstabview: vertical and horizontal headers must be different columns
 -- error: too many columns
 SELECT a,a,1 FROM generate_series(1,3000) AS a
  \crosstabview
-Maximum number of columns (1600) exceeded
+\crosstabview: maximum number of columns (1600) exceeded
 -- error: only one column
 SELECT 1 \crosstabview
-The query must return at least two columns to be shown in crosstab
+\crosstabview: query must return at least three columns
 DROP TABLE ctv_data;

src/test/regress/sql/psql_crosstab.sql

@@ -23,7 +23,7 @@ SELECT v, EXTRACT(year FROM d), count(*)
 -- ordered months in horizontal header, quoted column name
 SELECT v, to_char(d, 'Mon') AS "month name", EXTRACT(month FROM d) AS num,
  count(*) FROM ctv_data  GROUP BY 1,2,3 ORDER BY 1
- \crosstabview v "month name":num 4
+ \crosstabview v "month name" 4 num
 
 -- ordered months in vertical header, ordered years in horizontal header
 SELECT EXTRACT(year FROM d) AS year, to_char(d,'Mon') AS "month name",
@@ -32,7 +32,7 @@ SELECT EXTRACT(year FROM d) AS year, to_char(d,'Mon') AS "month name",
   FROM ctv_data
   GROUP BY EXTRACT(year FROM d), to_char(d,'Mon'), EXTRACT(month FROM d)
 ORDER BY month
-\crosstabview "month name" year:year format
+\crosstabview "month name" year format year
 
 -- combine contents vertically into the same cell (V/H duplicates)
 SELECT v, h, string_agg(c, E'\n') FROM ctv_data GROUP BY v, h ORDER BY 1,2,3
@@ -41,17 +41,17 @@ SELECT v, h, string_agg(c, E'\n') FROM ctv_data GROUP BY v, h ORDER BY 1,2,3
 -- horizontal ASC order from window function
 SELECT v,h, string_agg(c, E'\n') AS c, row_number() OVER(ORDER BY h) AS r
 FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
- \crosstabview v h:r c
+ \crosstabview v h c r
 
 -- horizontal DESC order from window function
 SELECT v, h, string_agg(c, E'\n') AS c, row_number() OVER(ORDER BY h DESC) AS r
 FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
- \crosstabview v h:r c
+ \crosstabview v h c r
 
 -- horizontal ASC order from window function, NULLs pushed rightmost
 SELECT v,h, string_agg(c, E'\n') AS c, row_number() OVER(ORDER BY h NULLS LAST) AS r
 FROM ctv_data GROUP BY v, h ORDER BY 1,3,2
- \crosstabview v h:r c
+ \crosstabview v h c r
 
 -- only null, no column name, 2 columns: error
 SELECT null,null \crosstabview
@@ -76,10 +76,22 @@ SELECT v,h, string_agg(i::text, E'\n') AS i, string_agg(c, E'\n') AS c
 FROM ctv_data GROUP BY v, h ORDER BY h,v
  \crosstabview 1 "h" 4
 
+-- refer to columns by quoted names, check downcasing of unquoted name
+SELECT 1 as "22", 2 as b, 3 as "Foo"
+ \crosstabview "22" B "Foo"
+
 -- error: bad column name
 SELECT v,h,c,i FROM ctv_data
  \crosstabview v h j
 
+-- error: need to quote name
+SELECT 1 as "22", 2 as b, 3 as "Foo"
+ \crosstabview 1 2 Foo
+
+-- error: need to not quote name
+SELECT 1 as "22", 2 as b, 3 as "Foo"
+ \crosstabview 1 "B" "Foo"
+
 -- error: bad column number
 SELECT v,h,i,c FROM ctv_data
  \crosstabview 2 1 5