現在、ビューを作成しています 回答のここを参照してください 。 crosstab()
クエリに基づいて関数を作成して、日付を渡し、特定の日付のデータを取得するにはどうすればよいですか?
また、その関数を複数回呼び出して、異なる日付を渡してチャートを埋めるのもよい習慣ですか(たとえば)。
私はSQL関数を提案します:
_CREATE OR REPLACE FUNCTION foo(_date date)
RETURNS TABLE (
name text -- types have to match your actual types!
, keyword_id int
, project_id int
, the_date date
, today int
, yesterday int
, week int
, month int) AS
$func$
SELECT k.name, f.keyword_id, f.project_id, _date -- AS the_date -- col alias irrelevant
, f.t AS today, f.y As yesterday, f.w AS week, f.m AS month
FROM crosstab(
-- crosstab function from previous question here
-- http://dba.stackexchange.com/a/71266/3684
) f (rn int, keyword_id int, project_id int
, t int, y int, w int, m int)
JOIN keyword k USING (keyword_id);
$func$ LANGUAGE sql;
_
コール:
_SELECT * FROM foo('2014-07-07');
_
すべてのnow()::date
を__date
_という名前の入力パラメーターに置き換えます。
Postgres 9.1以前では、SQL関数で位置パラメータ_$1
_を使用します(どのバージョンでも使用できます)。
その他のコード例:
crosstab()
関数は、クエリstringsをパラメーターとして受け取ります。関数パラメーターはcrosstab()
内では表示されません。したがって、日付値をstring literalsとして渡す必要があります!
便宜上、関数format()
をお勧めします。たとえば、2番目のパラメータは次のようになります。
_,format('VALUES(%L::date), (%L), (%L), (%L)'
, $1, $1 - 1, $1 - 7, ($1 - interval '1 month')::date
)
_
の代わりに:
_,$$
VALUES
(now()::date)
, (now()::date - 1)
, (now()::date - 7)
, ((now() - interval '1 month')::date)
$$
_
_CREATE OR REPLACE FUNCTION foo_sql(_date date)
RETURNS TABLE (
name text
, keyword_id int
, project_id int
, the_date date
, today int
, yesterday int
, week int
, month int) AS
$func$
BEGIN
SELECT k.name, f.keyword_id, f.project_id, _date
, f.t, f.y, f.w, f.m
FROM crosstab (
$$
SELECT rn
, pk.keyword_id
, pk.project_id
, d.created_at
, COALESCE(pr.pos, 0)
FROM (SELECT *, row_number() OVER () AS rn FROM project_keyword) pk
CROSS JOIN (
$$
|| format('VALUES(%L::date), (%L), (%L), (%L)'
, $1, $1 - 1, $1 - 7, ($1 - interval '1 month')::date)
|| $$
) d(created_at)
LEFT JOIN (
SELECT keyword_id
, project_id
, created_at::date AS created_at
, min(position) AS pos
FROM project_report
GROUP BY keyword_id, project_id, created_at::date
) pr USING (keyword_id, project_id, created_at)
ORDER BY pk.rn, d.created_at
$$
,format('VALUES(%L::date), (%L), (%L), (%L)'
, $1, $1 - 1, $1 - 7, ($1 - interval '1 month')::date)
) f (rn int, keyword_id int, project_id int
, t int, y int, w int, m int)
JOIN keyword k USING (keyword_id);
END
$func$ LANGUAGE sql;
_
より短く、VALUES
式を再利用します。おそらくもう少し速いです。
_CREATE OR REPLACE FUNCTION foo_plpgsql(_date date)
RETURNS TABLE (name text, keyword_id int, project_id int, the_date date
, today int, yesterday int, week int, month int) AS
$func$
DECLARE
_dates text := format('VALUES(%L::date), (%L), (%L), (%L)'
, $1, $1 - 1, $1 - 7, ($1 - interval '1 month')::date);
BEGIN
SELECT k.name, f.keyword_id, f.project_id, _date, f.t, f.y, f.w, f.m
FROM crosstab (
'SELECT rn
, pk.keyword_id
, pk.project_id
, d.created_at
, COALESCE(pr.pos, 0)
FROM (SELECT *, row_number() OVER () AS rn FROM project_keyword) pk
CROSS JOIN (
' || _dates || '
) d(created_at)
LEFT JOIN (
SELECT keyword_id
, project_id
, created_at::date AS created_at
, min(position) AS pos
FROM project_report
GROUP BY keyword_id, project_id, created_at::date
) pr USING (keyword_id, project_id, created_at)
ORDER BY pk.rn, d.created_at'
,_dates
) f (rn int, keyword_id int, project_id int, t int, y int, w int, m int)
JOIN keyword k USING (keyword_id);
END
$func$ LANGUAGE plpgsql;
_
完全を期すために、関数を永続化せずに「同じ」を CTEs で指定します。
_WITH d(day) AS (SELECT '2014-07-07'::date) -- provide your date here
, v(dates) AS (
SELECT format('VALUES(%L::date), (%L), (%L), (%L)'
, day, day - 1, day - 7
,(day - interval '1 month')::date)
FROM d
)
SELECT k.name, f.keyword_id, f.project_id, d.day AS the_date
, f.t AS today, f.y As yesterday, f.w AS week, f.m AS month
FROM crosstab (
'SELECT rn
, pk.keyword_id
, pk.project_id
, d.created_at
, COALESCE(pr.pos, 0) AS pos
FROM (SELECT *, row_number() OVER () AS rn FROM project_keyword) pk
CROSS JOIN (
' || (SELECT dates FROM v) || '
) d(created_at)
LEFT JOIN (
SELECT keyword_id
, project_id
, created_at::date AS created_at
, min(position) AS pos
FROM project_report
GROUP BY keyword_id, project_id, created_at::date
) pr USING (keyword_id, project_id, created_at)
ORDER BY pk.rn, d.created_at'
,(SELECT dates FROM v)
) f (rn int, keyword_id int, project_id int
, t int, y int, w int, m int)
JOIN keyword k USING (keyword_id);
_