<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
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>
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>
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>
int num_columns, pivot_field *piv_columns, int field_for_columns,
int num_rows, pivot_field *piv_rows, int field_for_rows,
int field_for_data);
-static int parseColumnRefs(const char *arg, const PGresult *res,
- int **col_numbers,
- int max_columns, char separator);
static void avlInit(avl_tree *tree);
static void avlMergeValue(avl_tree *tree, char *name, char *sort_value);
static int avlCollectFields(avl_tree *tree, avl_node *node,
pivot_field *fields, int idx);
static void avlFree(avl_tree *tree, avl_node *node);
static void rankSort(int num_columns, pivot_field *piv_columns);
-static int indexOfColumn(const char *arg, const PGresult *res);
+static int indexOfColumn(char *arg, const PGresult *res);
static int pivotFieldCompare(const void *a, const void *b);
static int rankCompare(const void *a, const void *b);
/*
* Main entry point to this module.
*
- * Process the data from *res according the display options in pset (global),
+ * Process the data from *res according to the options in pset (global),
* to generate the horizontal and vertical headers contents,
* then call printCrosstab() for the actual output.
*/
bool
PrintResultsInCrosstab(const PGresult *res)
{
- char *opt_field_for_rows = pset.ctv_col_V;
- char *opt_field_for_columns = pset.ctv_col_H;
- char *opt_field_for_data = pset.ctv_col_D;
- int rn;
+ bool retval = false;
avl_tree piv_columns;
avl_tree piv_rows;
pivot_field *array_columns = NULL;
pivot_field *array_rows = NULL;
int num_columns = 0;
int num_rows = 0;
- int *colsV = NULL,
- *colsH = NULL,
- *colsD = NULL;
- int n;
- int field_for_columns;
- int sort_field_for_columns = -1;
int field_for_rows;
- int field_for_data = -1;
- bool retval = false;
+ int field_for_columns;
+ int field_for_data;
+ int sort_field_for_columns;
+ int rn;
avlInit(&piv_rows);
avlInit(&piv_columns);
- if (res == NULL)
- {
- psql_error(_("No result\n"));
- goto error_return;
- }
-
if (PQresultStatus(res) != PGRES_TUPLES_OK)
{
- psql_error(_("The query must return results to be shown in crosstab\n"));
+ psql_error(_("\\crosstabview: query must return results to be shown in crosstab\n"));
goto error_return;
}
- if (opt_field_for_rows && !opt_field_for_columns)
+ if (PQnfields(res) < 3)
{
- psql_error(_("A second column must be specified for the horizontal header\n"));
+ psql_error(_("\\crosstabview: query must return at least three columns\n"));
goto error_return;
}
- if (PQnfields(res) <= 2)
- {
- psql_error(_("The query must return at least two columns to be shown in crosstab\n"));
- goto error_return;
- }
-
- /*
- * Arguments processing for the vertical header (1st arg) displayed in the
- * left-most column. Only a reference to a field is accepted (no sort
- * column).
- */
-
- if (opt_field_for_rows == NULL)
- {
+ /* Process first optional arg (vertical header column) */
+ if (pset.ctv_args[0] == NULL)
field_for_rows = 0;
- }
else
{
- n = parseColumnRefs(opt_field_for_rows, res, &colsV, 1, ':');
- if (n != 1)
+ field_for_rows = indexOfColumn(pset.ctv_args[0], res);
+ if (field_for_rows < 0)
goto error_return;
- field_for_rows = colsV[0];
}
- if (field_for_rows < 0)
- goto error_return;
-
- /*----------
- * Arguments processing for the horizontal header (2nd arg)
- * (pivoted column that gets displayed as the first row).
- * Determine:
- * - the field number for the horizontal header column
- * - the field number of the associated sort column, if any
- */
-
- if (opt_field_for_columns == NULL)
+ /* Process second optional arg (horizontal header column) */
+ if (pset.ctv_args[1] == NULL)
field_for_columns = 1;
else
{
- n = parseColumnRefs(opt_field_for_columns, res, &colsH, 2, ':');
- if (n <= 0)
- goto error_return;
- if (n == 1)
- field_for_columns = colsH[0];
- else
- {
- field_for_columns = colsH[0];
- sort_field_for_columns = colsH[1];
- }
-
+ field_for_columns = indexOfColumn(pset.ctv_args[1], res);
if (field_for_columns < 0)
goto error_return;
}
+ /* Insist that header columns be distinct */
if (field_for_columns == field_for_rows)
{
- psql_error(_("The same column cannot be used for both vertical and horizontal headers\n"));
+ psql_error(_("\\crosstabview: vertical and horizontal headers must be different columns\n"));
goto error_return;
}
- /*
- * Arguments processing for the data columns (3rd arg). Determine the
- * column to display in the grid.
- */
- if (opt_field_for_data == NULL)
+ /* Process third optional arg (data column) */
+ if (pset.ctv_args[2] == NULL)
{
- int i;
+ int i;
/*
* If the data column was not specified, we search for the one not
- * used as either vertical or horizontal headers. If the result has
- * more than three columns, raise an error.
+ * used as either vertical or horizontal headers. Must be exactly
+ * three columns, or this won't be unique.
*/
- if (PQnfields(res) > 3)
+ if (PQnfields(res) != 3)
{
- psql_error(_("Data column must be specified when the result set has more than three columns\n"));
+ psql_error(_("\\crosstabview: data column must be specified when query returns more than three columns\n"));
goto error_return;
}
+ field_for_data = -1;
for (i = 0; i < PQnfields(res); i++)
{
if (i != field_for_rows && i != field_for_columns)
}
else
{
- int num_fields;
+ field_for_data = indexOfColumn(pset.ctv_args[2], res);
+ if (field_for_data < 0)
+ goto error_return;
+ }
- /* If a field was given, find out what it is. Only one is allowed. */
- num_fields = parseColumnRefs(opt_field_for_data, res, &colsD, 1, ',');
- if (num_fields < 1)
+ /* Process fourth optional arg (horizontal header sort column) */
+ if (pset.ctv_args[3] == NULL)
+ sort_field_for_columns = -1; /* no sort column */
+ else
+ {
+ sort_field_for_columns = indexOfColumn(pset.ctv_args[3], res);
+ if (sort_field_for_columns < 0)
goto error_return;
- field_for_data = colsD[0];
}
/*
if (piv_columns.count > CROSSTABVIEW_MAX_COLUMNS)
{
- psql_error(_("Maximum number of columns (%d) exceeded\n"),
+ psql_error(_("\\crosstabview: maximum number of columns (%d) exceeded\n"),
CROSSTABVIEW_MAX_COLUMNS);
goto error_return;
}
avlFree(&piv_rows, piv_rows.root);
pg_free(array_columns);
pg_free(array_rows);
- pg_free(colsV);
- pg_free(colsH);
- pg_free(colsD);
return retval;
}
*/
if (cont.cells[idx] != NULL)
{
- psql_error(_("data cell already contains a value: (row: \"%s\", column: \"%s\")\n"),
+ psql_error(_("\\crosstabview: query result contains multiple data values for row \"%s\", column \"%s\"\n"),
piv_rows[row_number].name ? piv_rows[row_number].name :
popt.nullPrint ? popt.nullPrint : "(null)",
piv_columns[col_number].name ? piv_columns[col_number].name :
return retval;
}
-/*
- * Parse "arg", which is a string of column IDs separated by "separator".
- *
- * Each column ID can be:
- * - a number from 1 to PQnfields(res)
- * - an unquoted column name matching (case insensitively) one of PQfname(res,...)
- * - a quoted column name matching (case sensitively) one of PQfname(res,...)
- *
- * If max_columns > 0, it is the max number of column IDs allowed.
- *
- * On success, return number of column IDs found (possibly 0), and return a
- * malloc'd array of the matching column numbers of "res" into *col_numbers.
- *
- * On failure, return -1 and set *col_numbers to NULL.
- */
-static int
-parseColumnRefs(const char *arg,
- const PGresult *res,
- int **col_numbers,
- int max_columns,
- char separator)
-{
- const char *p = arg;
- char c;
- int num_cols = 0;
-
- *col_numbers = NULL;
- while ((c = *p) != '\0')
- {
- const char *field_start = p;
- bool quoted_field = false;
-
- /* first char */
- if (c == '"')
- {
- quoted_field = true;
- p++;
- }
-
- while ((c = *p) != '\0')
- {
- if (c == separator && !quoted_field)
- break;
- if (c == '"') /* end of field or embedded double quote */
- {
- p++;
- if (*p == '"')
- {
- if (quoted_field)
- {
- p++;
- continue;
- }
- }
- else if (quoted_field && *p == separator)
- break;
- }
- if (*p)
- p += PQmblen(p, pset.encoding);
- }
-
- if (p != field_start)
- {
- char *col_name;
- int col_num;
-
- /* enforce max_columns limit */
- if (max_columns > 0 && num_cols == max_columns)
- {
- psql_error(_("No more than %d column references expected\n"),
- max_columns);
- goto errfail;
- }
- /* look up the column and add its index into *col_numbers */
- col_name = pg_malloc(p - field_start + 1);
- memcpy(col_name, field_start, p - field_start);
- col_name[p - field_start] = '\0';
- col_num = indexOfColumn(col_name, res);
- pg_free(col_name);
- if (col_num < 0)
- goto errfail;
- *col_numbers = (int *) pg_realloc(*col_numbers,
- (num_cols + 1) * sizeof(int));
- (*col_numbers)[num_cols++] = col_num;
- }
- else
- {
- psql_error(_("Empty column reference\n"));
- goto errfail;
- }
-
- if (*p)
- p += PQmblen(p, pset.encoding);
- }
- return num_cols;
-
-errfail:
- pg_free(*col_numbers);
- *col_numbers = NULL;
- return -1;
-}
-
/*
* The avl* functions below provide a minimalistic implementation of AVL binary
* trees, to efficiently collect the distinct values that will form the horizontal
}
/*
- * Compare a user-supplied argument against a field name obtained by PQfname(),
- * which is already case-folded.
- * If arg is not enclosed in double quotes, pg_strcasecmp applies, otherwise
- * do a case-sensitive comparison with these rules:
- * - double quotes enclosing 'arg' are filtered out
- * - double quotes inside 'arg' are expected to be doubled
- */
-static bool
-fieldNameEquals(const char *arg, const char *fieldname)
-{
- const char *p = arg;
- const char *f = fieldname;
- char c;
-
- if (*p++ != '"')
- return (pg_strcasecmp(arg, fieldname) == 0);
-
- while ((c = *p++))
- {
- if (c == '"')
- {
- if (*p == '"')
- p++; /* skip second quote and continue */
- else if (*p == '\0')
- return (*f == '\0'); /* p is shorter than f, or is
- * identical */
- }
- if (*f == '\0')
- return false; /* f is shorter than p */
- if (c != *f) /* found one byte that differs */
- return false;
- f++;
- }
- return (*f == '\0');
-}
-
-/*
- * arg can be a number or a column name, possibly quoted (like in an ORDER BY clause)
- * Returns:
- * on success, the 0-based index of the column
- * or -1 if the column number or name is not found in the result's structure,
- * or if it's ambiguous (arg corresponding to several columns)
+ * Look up a column reference, which can be either:
+ * - a number from 1 to PQnfields(res)
+ * - a column name matching one of PQfname(res,...)
+ *
+ * Returns zero-based column number, or -1 if not found or ambiguous.
+ *
+ * Note: may modify contents of "arg" string.
*/
static int
-indexOfColumn(const char *arg, const PGresult *res)
+indexOfColumn(char *arg, const PGresult *res)
{
int idx;
- if (strspn(arg, "0123456789") == strlen(arg))
+ if (arg[0] && strspn(arg, "0123456789") == strlen(arg))
{
/* if arg contains only digits, it's a column number */
idx = atoi(arg) - 1;
if (idx < 0 || idx >= PQnfields(res))
{
- psql_error(_("Invalid column number: %s\n"), arg);
+ psql_error(_("\\crosstabview: invalid column number: \"%s\"\n"), arg);
return -1;
}
}
else
{
+ bool inquotes = false;
+ char *cp = arg;
int i;
+ /*
+ * Dequote and downcase the column name. By checking for all-digits
+ * before doing this, we can ensure that a quoted name is treated as a
+ * name even if it's all digits. This transformation should match
+ * what psqlscanslash.l does in OT_SQLID mode. (XXX ideally we would
+ * let the lexer do this, but then we couldn't tell if the name was
+ * quoted.)
+ */
+ while (*cp)
+ {
+ if (*cp == '"')
+ {
+ if (inquotes && cp[1] == '"')
+ {
+ /* Keep the first quote, remove the second */
+ cp++;
+ }
+ inquotes = !inquotes;
+ /* Collapse out quote at *cp */
+ memmove(cp, cp + 1, strlen(cp));
+ /* do not advance cp */
+ }
+ else
+ {
+ if (!inquotes)
+ *cp = pg_tolower((unsigned char) *cp);
+ cp += PQmblen(cp, pset.encoding);
+ }
+ }
+
+ /* Now look for match(es) among res' column names */
idx = -1;
for (i = 0; i < PQnfields(res); i++)
{
- if (fieldNameEquals(arg, PQfname(res, i)))
+ if (strcmp(arg, PQfname(res, i)) == 0)
{
if (idx >= 0)
{
- /* if another idx was already found for the same name */
- psql_error(_("Ambiguous column name: %s\n"), arg);
+ /* another idx was already found for the same name */
+ psql_error(_("\\crosstabview: ambiguous column name: \"%s\"\n"), arg);
return -1;
}
idx = i;
}
if (idx == -1)
{
- psql_error(_("Invalid column name: %s\n"), arg);
+ psql_error(_("\\crosstabview: column name not found: \"%s\"\n"), arg);
return -1;
}
}
-- 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
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
-- 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
-- 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+| | |
-- 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
-- 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? |
| | | | 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;
-- 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",
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
-- 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
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
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