gbase数据、南大通用产品文档：GBase8c

获取帮助
使用SQLdiag 工具前，您可以通过以下指令获取帮助。
gs_dbmind component sqldiag --help
显示如下帮助信息：
usage:
[-h] [-f CSV_FILE] [--predicted-file PREDICTED_FILE]
[--model {template,dnn}] --model-path MODEL_PATH
[--config-file CONFIG_FILE]
{train,predict,finetune}
SQLdiag integrated by openGauss.
positional arguments:
{train,predict,finetune}
The training mode is to perform feature extraction and
model training based on historical SQL statements. The
prediction mode is to predict the execution time of a
new SQL statement through the trained model.
optional arguments:
-h, --help
show this help message and exit
-f CSV_FILE, --csv-file CSV_FILE
The data set for training or prediction. The file
format is CSV. If it is two columns, the format is
(SQL statement, duration time). If it is three

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南大通用数据技术股份有限公司
398
columns, the format is (timestamp of SQL statement
execution time, SQL statement, duration time).
--predicted-file PREDICTED_FILE
The file path to save the predicted result.
--model {template,dnn}
Choose the model model to use.
--model-path MODEL_PATH
The storage path of the model file, used to read or
save the model file.
--config-file CONFIG_FILE

|
+------+------+------+--------+-------------------------------------
800000 rows in set
导出SQL 语句：
gbase> SELECT * FROM test INTO OUTFILE '/home/gbase/temp/test.tbl'
fields terminated by ‘|’ with head;
Query OK, 800000 rows affected
查看导出文件：
$ cat test.tbl
ps_partkey| ps_suppkey| ps_availqty| ps_supplycost| ps_comment
1|2|3325|771.64|, even theodolites. Regular

GBase 8a MPP Cluster 产品手册
5 数据库管理指南
文档版本953（2022-09-15）
南大通用数据技术股份有限公司
1241
1|2502|8076|993.49|ven ideas. quickly
1|5002|3956|337.09|after the fluffily ironic
......
......

返回值
取模。返回N 除以M 后的余数。
示例
示例1
返回234 除以10 的余数。
gbase> SELECT MOD(234, 10) FROM t;
+--------------+
| MOD(234, 10) |
+--------------+
| 4 |
+--------------+
1 row in set
示例2
返回253 除以7 的余数。
gbase> SELECT 253 % 7 FROM t;
+---------+
| 253 % 7 |
+---------+
| 1 |
+---------+
1 row in set
示例3
gbase> SELECT MOD(29,9) FROM t;

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文档版本04（2021-04-21） 南大通用数据技术股份有限公司 464
+-----------+
| MOD(29,9) |
+-----------+
| 2 |
+-----------+
1 row in set

gbase> SELECT 29 MOD 9 FROM t;
+----------+
| 29 MOD 9 |
+----------+
| 2 |
+----------+
1 row in set
示例4
MOD()也适用于小数部分，返回除法运算后的精确余数。
gbase> SELECT MOD(34.5,3) FROM t;
+-------------+
| MOD(34.5,3) |
+-------------+
| 1.5 |
+-------------+
1 row in set
示例5
取模的三种表现形式。
gbase> SELECT 253 % 7, MOD(253,7), 253 MOD 7 FROM t;
+---------+------------+-----------+
| 253 % 7 | MOD(253,7) | 253 MOD 7 |
+---------+------------+-----------+
| 1 | 1 | 1 |
+---------+------------+-----------+
1 row in set