英文:
Failure to Use a Stored Procedure in GridDB
问题
由于我之前曾与关系型数据库一起工作,使用存储过程是一种常见的做法,但相当长一段时间以来,我已经转向使用GridDB,一个NoSQL数据库。我最近遇到的问题是使用存储过程时出现了以下错误:
[错误代码]: 151001
[描述](语法错误)
我认为在GridDB中存储过程是不支持的操作。是否有一种方法可以在GridDB中创建用户定义的函数(UDF),有人可以帮助提供下面我的代码示例的编辑,以在查询期间执行自定义数据处理操作吗?
import com.toshiba.mwcloud.gs.Collection;
import com.toshiba.mwcloud.gs.GSException;
import com.toshiba.mwcloud.gs.GridStore;
import com.toshiba.mwcloud.gs.GridStoreFactory;
import com.toshiba.mwcloud.gs.Query;
import com.toshiba.mwcloud.gs.RowKey;
import com.toshiba.mwcloud.gs.RowSet;
static class Order{
int order_id;
int total_amount;
}
Properties props = new Properties();
props.setProperty("notificationAddress", "239.0.0.1");
props.setProperty("notificationPort", "31999");
props.setProperty("clusterName", "defaultCluster");
props.setProperty("user", "admin");
props.setProperty("password", "admin");
GridStore store = GridStoreFactory.getInstance().getGridStore(props);
CREATE PROCEDURE CalculateOrderTotal(IN orderId INT, OUT totalAmount DECIMAL(10, 2))
BEGIN
DECLARE itemPrice DECIMAL(10, 2);
SET totalAmount = 0;
DECLARE done INT DEFAULT FALSE;
SELECT price FROM OrderItems WHERE order_id = orderId;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
END
query = f"SELECT order_id, total_amount {CalculateOrderTotal}(quantity, price) AS total_price FROM {myCluster}"
results = container.query(query)
英文:
Since I have previously worked with relational databases, using stored procedures is a common practice, but for quite a long time, I have shifted to using GridDB, a NoSQL database. The problem that I recently faced was the use of a stored procedure which gave me the following error:
[Error code]: 151001
[Description] (Syntax error)
I think the stored procedure is an unsupported operation in GridDB. Is there a way of creating a user-defined function (UDF) in GridDB, and can anyone help provide edits in my code example below on how to use it to perform a custom data processing operation during the query?
import com.toshiba.mwcloud.gs.Collection;
import com.toshiba.mwcloud.gs.GSException;
import com.toshiba.mwcloud.gs.GridStore;
import com.toshiba.mwcloud.gs.GridStoreFactory;
import com.toshiba.mwcloud.gs.Query;
import com.toshiba.mwcloud.gs.RowKey;
import com.toshiba.mwcloud.gs.RowSet;
static class Order{
int order_id;
int total_amount;
}
Properties props = new Properties();
props.setProperty("notificationAddress", "239.0.0.1");
props.setProperty("notificationPort", "31999");
props.setProperty("clusterName", "defaultCluster");
props.setProperty("user", "admin");
props.setProperty("password", "admin");
GridStore store = GridStoreFactory.getInstance().getGridStore(props);
CREATE PROCEDURE CalculateOrderTotal(IN orderId INT, OUT totalAmount DECIMAL(10, 2))
BEGIN
DECLARE itemPrice DECIMAL(10, 2);
SET totalAmount = 0;
DECLARE done INT DEFAULT FALSE;
SELECT price FROM OrderItems WHERE order_id = orderId;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
END
query = f"SELECT order_id, total_amount {CalculateOrderTotal}(quantity, price) AS total_price FROM {myCluster}"
results = container.query(query)
答案1
得分: 1
我将为您创建一个UDF,该UDF根据订单中每个商品的数量和价格计算总价格:
import com.toshiba.mwcloud.gs.GridStore;
import com.toshiba.mwcloud.gs.GridStoreFactory;
import com.toshiba.mwcloud.gs.GridStoreFactoryFactory;
import com.toshiba.mwcloud.gs.Row;
import com.toshiba.mwcloud.gs.RowSet;
import com.toshiba.mwcloud.gs.TimeSeries;
String totalPriceFunction = "function calculateTotalPrice(quantity, price) { return quantity * price; }";
GridStore store = GridStoreFactory.getInstance().getGridStore(props);
store.putFunction("calculateTotalPrice", totalPriceFunction, null);
String containerName = "OrderItems";
TimeSeries<Row> container = store.putTimeSeries(containerName, Row.class);
然后,在您的查询中调用它以计算总价格:
import com.toshiba.mwcloud.gs.Query;
import com.toshiba.mwcloud.gs.RowKey;
import com.toshiba.mwcloud.gs.RowSet;
String queryStr = String.format("SELECT order_id, calculateTotalPrice(quantity, price) AS total_price FROM %s", containerName);
Query<Row> query = store.query(queryStr, Row.class);
RowSet<Row> rs = query.fetch();
while (rs.hasNext()) {
Row row = rs.next();
int orderId = row.getInteger("order_id");
double totalPrice = row.getDouble("total_price");
// 使用 orderId 和 totalPrice 进行其他操作
}
请注意,上述代码是用Java编写的,并且在查询中使用了创建的UDF函数来计算总价格。
英文:
I would create a udf that calculates the total price based on the quantity and price of each item in the order:
import com.toshiba.mwcloud.gs.GridStore;
import com.toshiba.mwcloud.gs.GridStoreFactory;
import com.toshiba.mwcloud.gs.GridStoreFactoryFactory;
import com.toshiba.mwcloud.gs.Row;
import com.toshiba.mwcloud.gs.RowSet;
import com.toshiba.mwcloud.gs.TimeSeries;
String totalPriceFunction = "function calculateTotalPrice(quantity, price) { return quantity * price; }";
GridStore store = GridStoreFactory.getInstance().getGridStore(props);
store.putFunction("calculateTotalPrice", totalPriceFunction, null);
String containerName = "OrderItems";
TimeSeries<Row> container = store.putTimeSeries(containerName, Row.class);
then call it in your query to calculate total price:
import com.toshiba.mwcloud.gs.Query;
import com.toshiba.mwcloud.gs.RowKey;
import com.toshiba.mwcloud.gs.RowSet;
String queryStr = String.format("SELECT order_id, calculateTotalPrice(quantity, price) AS total_price FROM %s", containerName);
Query<Row> query = store.query(queryStr, Row.class);
RowSet<Row> rs = query.fetch();
while (rs.hasNext()) {
Row row = rs.next();
int orderId = row.getInteger("order_id");
double totalPrice = row.getDouble("total_price");
// do something with orderId and totalPrice
}
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