[SQLite] CASTで型変換
SQLiteで型を変換するのは、CAST関数を使います。
日付変換
- ハイフン区切り
SELECT cast("2024/1/1" as DATE) as date
> "2024-01-01"
- アンダースコア区切り
SELECT cast("2024_1_1" as DATE) as date
> "2024-01-01"
- 半角スペース区切り(変換されない)
SELECT cast("2024 1 1" as DATE) as date
> null
- %区切り
SELECT cast("2024%1%1" as DATE) as date
> "2024-01-01"
- 日本語表記(変換されない)
SELECT cast("2024年1月1日" as DATE) as date
> null
- UTC表記
SELECT cast("2024-01-01 00:00:00 UTC" as DATE) as date
> "2024-01-01"
文字列→数値
- INTEGER(変換されない)
SELECT cast("001" as INTEGER) as num
> null
- FLOAT
SELECT cast("001" as FLOAT) as num
> 1
- DOUBLE
SELECT cast("001" as DOUBLE) as num
> 1