?????? ?? ??? ???? Java ??:
public static boolean isExistDatabase(String database) {
Connection conn = null;
Statement stmt = null;
ResultSet rs = null;// 數(shù)據(jù)庫(kù)結(jié)果集
try {
conn = getConnection();
stmt = conn.createStatement();
String sql = "SELECT COUNT(*) FROM information_schema.schemata WHERE schema_name=\"" + database + "\"";
System.out.println(sql);
rs = stmt.executeQuery(sql);
if (rs.next()) {
if (rs.getInt(1) == 0) {
return false;
} else {
return true;
}
}
return false;
} catch (Exception e) {
throw new TenantException(e.getMessage(), Status.INTERNAL_SERVER_ERROR);
} finally {
try {
if (rs != null) {
rs.close();
}
if (stmt != null) {
stmt.close();
}
if (conn != null) {
conn.close();
}
} catch (SQLException e) {
throw new TenantException("mysql關(guān)閉連接失敗：" + e.getMessage(), Status.INTERNAL_SERVER_ERROR);
}
}
}?? SQL ??:
String sql = "SELECT COUNT(*) FROM information_schema.schemata WHERE schema_name=\"" + database + "\"";
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