IDENTITY_VAL_LOCAL関数

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æ§‹æ–‡:
 IDENTITY_VAL_LOCAL ( )

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IDENTITY_VAL_LOCAL関数��引数��り��ん。関数��果�対応�る識別列�データ型�よら�DECIMAL (31,0)��。

IDENTITY_VAL_LOCAL関数�より��る接続�返�れる値���行�INSERT文�識別列�代入�れ�最近�値��。INSERT文�識別列を��表��VALUES節を����れ��り��ん。 代入�れ�値�Derby�生���識別値��。 も�識別列を��表�対���行�INSERT文�発行�れ�����ら���関数�nullを返���。

��関数��果�以下�事柄�影響を����ん。
  • 識別列ã?®ã?ªã?„VALUES節をæŒ?ã?¤å?˜è¡Œã?®INSERTæ–‡
  • VALUES節をæŒ?ã?¤è¤‡æ•°è¡Œã?®INSERTæ–‡
  • selectã?«ã‚ˆã‚‹INSERTæ–‡
ã‚‚ã?—識別列をæŒ?ã?¤è¡¨ã?«INSERTトリガã?Œå®šç¾©ã?•れã?¦ã?Šã‚Šã€?ã??ã?®ãƒˆãƒªã‚¬ã?Œåˆ¥ã?®è­˜åˆ¥åˆ—ã‚’æŒ?ã?¤è¡¨ã?¸ã?®æŒ¿å…¥ã‚’行ã?†å ´å?ˆã€?IDENTITY_VAL_LOCAL()関数ã?¯æ–‡ã?§ç”Ÿæˆ?ã?•れã?Ÿå€¤ã‚’è¿”ã?—ã€?トリガã?«ã‚ˆã‚‹å€¤ã‚’è¿”ã?—ã?¾ã?›ã‚“。

例:

ij> create table t1(c1 int generated always as identity, c2 int);
0 rows inserted/updated/deleted
ij> insert into t1(c2) values (8);
1 row inserted/updated/deleted
ij> values IDENTITY_VAL_LOCAL();
1 
-------------------------------
1                              
1 row selected
ij> select IDENTITY_VAL_LOCAL()+1, IDENTITY_VAL_LOCAL()-1 from t1;
1                                |2                          
-------------------------------------------------------------------
2                                |0                                
1 row selected
ij> insert into t1(c2) values (IDENTITY_VAL_LOCAL());
1 row inserted/updated/deleted
ij> select * from t1;
C1             |C2             
-------------------------------
1              |8              
2              |1              
2 rows selected
ij> values IDENTITY_VAL_LOCAL();
1                        
-------------------------------
2                              
1 row selected
ij> insert into t1(c2) values (8), (9);
2 rows inserted/updated/deleted
ij> -- 複数�値�挿入���関数�返�値�変�ら��。
values IDENTITY_VAL_LOCAL();
1                        
-------------------------------
2                              
1 row selected
ij> select * from t1;
C1             |C2             
-------------------------------
1              |8              
2              |1              
3              |8              
4              |9              
4 rows selected
ij> insert into t1(c2) select c1 from t1;
4 rows inserted/updated/deleted
-- selectを元���挿入���関数�返�値�変�ら��。
ij> values IDENTITY_VAL_LOCAL();
1                        
-------------------------------
2                              
1 row selected
ij> select * from t1;
C1             |C2             
-------------------------------
1              |8              
2              |1              
3              |8              
4              |9              
5              |1              
6              |2              
7              |3              
8              |4              
8 rows selected