JDBC? ???? ?? ??? ??? ID? ???
? ?????? JDBC? ???? ?????? ???? ??? ? ???? ??? ID? ???? ??? ??? ?????. ?????? ???? ?? ?? ?? ?? ??? ????.
?? Statement#getGeneratedKeys()
?? ?? ?? ???? ??????? ?? Statement#getGeneratedKeys() ???? ??? ???? ?????. ? ???? ??? ?? ??? ResultSet? ?????. ????? ???? ??? ? Statement.RETURN_GENERATED_KEYS? ???? JDBC ????? ??? ?? ????? ???? ???.
??:
try (
Connection connection = dataSource.getConnection();
PreparedStatement statement = connection.prepareStatement(SQL_INSERT,
Statement.RETURN_GENERATED_KEYS);
) {
// Set statement parameters
// ...
int affectedRows = statement.executeUpdate();
if (affectedRows == 0) {
throw new SQLException("Record insertion failed, no rows affected.");
}
try (ResultSet generatedKeys = statement.getGeneratedKeys()) {
if (generatedKeys.next()) {
user.setId(generatedKeys.getLong(1));
} else {
throw new SQLException("Record insertion failed, no ID obtained.");
}
}
}
??????? ??
Statement#getGeneratedKeys()? ?? JDBC ?????? ????? ???? ?? ???? ?? ???? ?? ?????. ?? ?????? ???? ?? ?? ??? ????.
-
Oracle:
CallableStatement?? ??RETURNING? ????? ?? ?? ??SELECT CURRVAL(sequencename)??? ?????. -
MySQL ? DB2: ??? ??????? ?????
Statement#getGeneratedKeys()? ?????. -
PostgreSQL: ?? ?????
Statement#getGeneratedKeys()? ?????. - MSSQL: ??? ???? ??? ?? ????. ??? ??? ???? ???? ?????.
? ??? JDBC? ??? ? ?? ID? ???? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!
? AI ??
Undress AI Tool
??? ???? ??
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???? ?? ??? ??? ?? AI ?? ?
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???? ?? ???? ??? AI ?????.
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AI ? ???
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??? ??? AI ?? ?? ??? ???? ?? ???? ??? ?? ????!
?? ??
??? ??
???++7.3.1
???? ?? ?? ?? ???
SublimeText3 ??? ??
??? ??, ???? ?? ????.
???? 13.0.1 ???
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???? CS6
??? ? ?? ??
SublimeText3 Mac ??
? ??? ?? ?? ?????(SublimeText3)
??? ??
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