Postgresql 將時間戳修改爲日期格式

Postgresql 將時間戳修改爲日期格式

關鍵函數：TO_TIMESTAMP

	SELECT 
	now(),
	CASE WHEN LENGTH(t.tn_year) > 4 THEN to_char(TO_TIMESTAMP(tn_year::int8/1000),'yyyy')::int4 ELSE tn_year::int4 END, --年份
	d.id,
	t.tn_sanshitotalnum, 
	case when position('%' IN t.tn_onthejobleaderpercent ) > 0 THEN replace(t.tn_onthejobleaderpercent,'%','')::numeric / 100 END,
	t.tn_onthejobleadernum 
	FROM tn_taxcertificate t 
	INNER JOIN dim_taxcertificate d ON d.name = t.tn_orgstructname
	WHERE t.tn_year IS NOT NULL AND t.tn_year <> '';
	

1. position('%' IN t.tn_onthejobleaderpercent ) position判斷是否包含某個字符串
2. replace(t.tn_onthejobleaderpercent,'%','') 使用replace去掉特殊字符串