All Questions
18,636
questions
560
votes
7
answers
310k
views
533
votes
35
answers
574k
views
How to print a query string with parameter values when using Hibernate
Is it possible in Hibernate to print generated SQL queries with real values instead of question marks?
How would you suggest to print queries with real values if it is not possible with Hibernate API?...
- 15.4k
515
votes
17
answers
778k
views
How to convert java.util.Date to java.sql.Date?
I am trying to use a java.util.Date as input and then creating a query with it - so I need a java.sql.Date.
I was surprised to find that it couldn't do the conversion implicitly or explicitly - but ...
- 12.7k
440
votes
5
answers
645k
views
Hibernate show real SQL [duplicate]
if I set
<property name="show_sql">true</property>
in my hibernate.cfg.xml configuration file in the console I can see the SQL.
But it's not real SQL... Can I see the SQL code that will ...
- 9,052
437
votes
15
answers
371k
views
How to get the insert ID in JDBC?
I want to INSERT a record in a database (which is Microsoft SQL Server in my case) using JDBC in Java. At the same time, I want to obtain the insert ID. How can I achieve this using JDBC API?
- 8,246
320
votes
16
answers
569k
views
How do I get the size of a java.sql.ResultSet?
Shouldn't this be a pretty straightforward operation? However, I see there's neither a size() nor length() method.
- 15.1k
194
votes
5
answers
223k
views
How to execute IN() SQL queries with Spring's JDBCTemplate effectively?
I was wondering if there is a more elegant way to do IN() queries with Spring's JDBCTemplate. Currently I do something like that:
StringBuilder jobTypeInClauseBuilder = new StringBuilder();
for(int i ...
- 9,516
194
votes
15
answers
327k
views
How can I get the SQL of a PreparedStatement?
I have a general Java method with the following method signature:
private static ResultSet runSQLResultSet(String sql, Object... queryParams)
It opens a connection, builds a PreparedStatement using ...
- 81.5k
188
votes
13
answers
108k
views
What are the pros and cons of performing calculations in sql vs. in your application
shopkeeper table has following fields:
id (bigint),amount (numeric(19,2)),createddate (timestamp)
Let's say, I have the above table. I want to get the records for yesterday and
generate a report by ...
- 4,984
185
votes
7
answers
414k
views
org.postgresql.util.PSQLException: FATAL: sorry, too many clients already
I am trying to connect to a Postgresql database, I am getting the following Error:
Error:org.postgresql.util.PSQLException: FATAL: sorry, too many clients already
What does the error mean and how ...
- 4,739
169
votes
21
answers
8k
views
Joins are for lazy people?
I recently had a discussion with another developer who claimed to me that JOINs (SQL) are useless. This is technically true but he added that using joins is less efficient than making several requests ...
- 18.1k
169
votes
16
answers
331k
views
Java - escape string to prevent SQL injection
I'm trying to put some anti sql injection in place in java and am finding it very difficult to work with the the "replaceAll" string function. Ultimately I need a function that will convert any ...
- 2,930
159
votes
20
answers
408k
views
SQLite in Android How to update a specific row
I've been trying to update a specific row for a while now, and it seems that there are two ways to do this. From what I've read and tried, you can just use the:
execSQL(String sql) method
or the:
...
- 18k
157
votes
10
answers
135k
views
How does a PreparedStatement avoid or prevent SQL injection?
I know that PreparedStatements avoid/prevent SQL Injection. How does it do that? Will the final form query that is constructed using PreparedStatements be a string or otherwise?
- 14.1k
150
votes
7
answers
109k
views
SQL parser library for Java [closed]
Is there an open-source Java library for parsing SQL statements?
If possible, it should be customizable or flexible enough to also be able to parse (or at least ignore) vendor-specific syntax (such ...
- 260k
136
votes
5
answers
345k
views
what is the use of annotations @Id and @GeneratedValue(strategy = GenerationType.IDENTITY)? Why the generationtype is identity?
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
Why we are using this annotations?
i need to know if this autoincrement my table id values.
(GenerationType.IDENTITY) is there any other types ...
- 6,628
125
votes
16
answers
966k
views
could not extract ResultSet in hibernate
I have a problem with Hibernate. I try to parse to List but It throws an exception: HTTP Status 500 - could not extract ResultSet. When I debug, It fault at line query.list()...
My sample code here
...
- 1,591
125
votes
15
answers
209k
views
Most efficient conversion of ResultSet to JSON?
The following code converts a ResultSet to a JSON string using JSONArray and JSONObject.
import org.json.JSONArray;
import org.json.JSONObject;
import org.json.JSONException;
import java.sql....
- 12k
124
votes
5
answers
146k
views
Android Room @Delete with parameters
I know I can't use DELETE in a query (that is a shame by the way), I will get the following error:
<i>Error:error: Observable query return type (LiveData, Flowable etc) can only be used with ...
- 1,545
123
votes
13
answers
187k
views
Spring JPA @Query with LIKE
I'm trying to make a method in CrudRepository that will be able to give me list of users, whose usernames are LIKE the input parameter(not only begin with, but also contains it). I tried to use method ...
- 2,340
123
votes
6
answers
242k
views
Multiple queries executed in java in single statement
Hi I was wondering if it is possible to execute something like this using JDBC as it currently provides an exception even though it is possible in the MySQL query browser.
"SELECT FROM * TABLE;INSERT ...
- 7,613
122
votes
14
answers
172k
views
Cleanest way to build an SQL string in Java
I want to build an SQL string to do database manipulation (updates, deletes, inserts, selects, that sort of thing) - instead of the awful string concat method using millions of "+"'s and quotes which ...
- 6,613
120
votes
5
answers
162k
views
Is there any good dynamic SQL builder library in Java? [closed]
Anyone knows some good SQL builder library for Java like Squiggle (not maintained anymore it seems). Preferably, a project in active development.
Preferably with syntax like Zend_Db_Select, something ...
- 29.7k
116
votes
7
answers
171k
views
Can I have H2 autocreate a schema in an in-memory database?
(I've already seen the H2 database In memory - Init schema via Spring/Hibernate question; it is not applicable here.)
I'd like to know if there's a setting in H2 that will allow me to auto-create a ...
- 15.8k
113
votes
15
answers
34k
views
Java Programming - Where should SQL statements be stored? [closed]
Where should an JDBC-compliant application store its SQL statements and why?
So far, I managed to identify these options:
Hardcoded in business objects
Embedded in SQLJ clauses
Encapsulate in ...
- 6,051
105
votes
19
answers
325k
views
How to call a stored procedure from Java and JPA
I am writing a simple web application to call a stored procedure and retrieve some data.
Its a very simple application, which interacts with client's database. We pass employee id and company id and ...
- 1,191
103
votes
32
answers
169k
views
The most sophisticated way for creating comma-separated Strings from a Collection/Array/List?
During my work with databases I noticed that I write query strings and in this strings I have to put several restrictions in the where-clause from a list/array/collection. Should look like this:
...
- 2,063
95
votes
11
answers
121k
views
Storing UUID as base64 String
I have been experimenting with using UUIDs as database keys. I want to take up the least amount of bytes as possible, while still keeping the UUID representation human readable.
I think that I have ...
- 14k
91
votes
12
answers
217k
views
Efficient way to do batch INSERTS with JDBC
In my app I need to do a lot of INSERTS. Its a Java app and I am using plain JDBC to execute the queries. The DB being Oracle. I have enabled batching though, so it saves me network latencies to ...
- 1,829
89
votes
4
answers
129k
views
A datetime equivalent in java.sql ? (is there a java.sql.datetime ?)
So far, I have not found a clear answer to this.
I'd like to know what the equivalent is for a SQL type DATETIME and the java type, using a PreparedStatement.
I have found: http://www.java2s.com/...
- 4,751
87
votes
10
answers
114k
views
handling DATETIME values 0000-00-00 00:00:00 in JDBC
I get an exception (see below) if I try to do
resultset.getString("add_date");
for a JDBC connection to a MySQL database containing a DATETIME value of 0000-00-00 00:00:00 (the quasi-null value for ...
- 187k
83
votes
9
answers
131k
views
How to get SQL from Hibernate Criteria API (*not* for logging)
Is there a way to get the (to-be-generated) SQL from a Hibernate Criteria?
Ideally, I would have something like:
Criteria criteria = session.createCriteria(Operator.class);
... build up the ...
- 3,068
82
votes
2
answers
118k
views
JPA 2 CriteriaQuery, using a limit
I am using JPA 2. For safety reasons, I am working type safe with CriteriaQuery's (and thus, I am not searching for any solutions to typed queries and so on).
I recently came across an issue in which ...
- 12.4k
75
votes
1
answer
56k
views
MySQL and JDBC with rewriteBatchedStatements=true
I've been reading around, here, here and here about the advantages of using rewriteBatchedStatements=true
If I understood it right, with rewriteBatchedStatements=true the JDBC will pack as many ...
- 7,900
71
votes
13
answers
72k
views
Running a .sql script using MySQL with JDBC
I am starting to use MySQL with JDBC.
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql:///x", "x", "x");
stmt = conn.createStatement();
stmt.execute( "CREATE ...
- 92.5k
70
votes
5
answers
121k
views
SQL JPA - Multiple columns as primary key
If i want severeal Column to make up an ID.
SQL example :
CONSTRAINT [PK_NAME] PRIMARY KEY ([Column1],[Column2],[Column3])
How can i do that with a Jpa Entity class ? through columndefinition ?
...
- 2,355
70
votes
7
answers
162k
views
How do you access the value of an SQL count () query in a Java program
I want to get to the value I am finding using the COUNT command of SQL. Normally I enter the column name I want to access into the getInt() getString() method, what do I do in this case when there is ...
- 50.7k
68
votes
8
answers
226k
views
How to convert Calendar to java.sql.Date in Java?
Calendar cal;
String sql = "INSERT INTO ttable (dt) values (?);"
//dt is a dateTime field in ttable
PreparedStatement stmt = connection.prepareStatement(sql);
stmt = setDate(1,cal); //not working
...
- 3,335
68
votes
6
answers
298k
views
Using setDate in PreparedStatement
In order to make our code more standard, we were asked to change all the places where we hardcoded our SQL variables to prepared statements and bind the variables instead.
I am however facing a ...
- 8,260
67
votes
4
answers
107k
views
Order By Date ASC with Spring Data
I try to make an application with Spring-Data-JPA on a table in order by ASC but it gives me an error:
Invalid derived query! No property asc found for type java.util.Calendar
Why ?
List<Foo> ...
- 5,033
67
votes
4
answers
98k
views
How to use a tablename variable for a java prepared statement insert [duplicate]
I am using a java PreparedStatment object to construct a series of batched INSERT queries. The query statement is of the format...
String strQuery = "INSERT INTO ? (col1, col2, col3, col4, col5) ...
- 835
66
votes
7
answers
92k
views
MS SQL Exception: Incorrect syntax near '@P0'
I'm querying a DB using MS SQL and for some reason I get the following error: com.microsoft.sqlserver.jdbc.SQLServerException: Incorrect syntax near '@P0' even though this 'P0' isn't anywhere in my ...
user818700
66
votes
10
answers
154k
views
Hibernate Union alternatives
What alternatives do I have to implement a union query using hibernate? I know hibernate does not support union queries at the moment, right now the only way I see to make a union is to use a view ...
- 18.2k
55
votes
4
answers
143k
views
JDBC ResultSet: I need a getDateTime, but there is only getDate and getTimeStamp
I would like to get the DATETIME column from an Oracle DB Table with JDBC. Here is my code:
int columnType = rsmd.getColumnType(i);
if(columnType == Types.DATE)
{
Date aDate = rs.getDate(i);
...
- 4,088
55
votes
9
answers
403k
views
java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/dbname [duplicate]
I have this Java program: MySQLConnectExample.java
import java.sql.*;
import java.util.Properties;
public class MySQLConnectExample {
public static void main(String[] args) {
Connection ...
- 567
55
votes
8
answers
68k
views
JDBC ResultSet get columns with table alias
Imagine I have a query like
SELECT * from table1 a, table2 b where (WHATEVER)
Maybe both tables have the same column name. So I though it would be nice to access the data via
resultSet.getString("...
- 10.8k
54
votes
3
answers
78k
views
54
votes
7
answers
30k
views
Can I use enum parameter into JpaRepository nativeQuery?
Entity looks like this:
@Getter
@Setter
@Entity
public class Application {
@Id
private Long id;
@Enumerated(EnumType.STRING)
private ApplicationStatus status;
}
Code works this way:
public ...
- 541
52
votes
2
answers
148k
views
JPQL SELECT between date statement [closed]
I would like to convert this SQL statement to a JPQL equivalent.
SELECT * FROM events
WHERE events_date BETWEEN '2011-01-01' AND '2011-03-31';
This correctly retrieves the information from the table ...
- 577
52
votes
5
answers
184k
views
Converting java date to Sql timestamp
I am trying to insert java.util.Date after converting it to java.sql.Timestamp and I am using the following snippet:
java.util.Date utilDate = new java.util.Date();
java.sql.Timestamp sq = new java....
- 817