NamedParameterJdbcTemplate (Spring JDBC)

NamedParameterJdbcTemplate is a Spring JDBC class that works like JdbcTemplate, but instead of using positional parameters (?), it allows you to use named parameters in SQL queries.

? In simple words:

NamedParameterJdbcTemplate = JdbcTemplate with readable, named SQL parameters

It makes SQL queries easier to read, safer to write, and easier to maintain, especially when queries become large or complex.

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Why Use NamedParameterJdbcTemplate?

Problems with JdbcTemplate

Stringsql="SELECT * FROM users WHERE name = ? AND status = ?";
jdbcTemplate.query(sql, name, status);

• Hard to read when there are many ?
• Easy to mix up parameter order
• Difficult to maintain large queries

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Solution with Named Parameters

Stringsql="SELECT * FROM users WHERE name = :name AND status = :status";

• SQL is self-explanatory
• Parameter order does not matter
• Reduces bugs caused by wrong indexing
• Much easier to maintain

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How NamedParameterJdbcTemplate Works (Internally)

ClientCode
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NamedParameterJdbcTemplate
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JdbcTemplate
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DataSource
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Database

• Converts named parameters (:name) into positional parameters (?)
• Delegates execution to JdbcTemplate
• Keeps full control over SQL

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Key Features

Feature	Description
Named Parameters	Uses :paramName instead of ?
Readable SQL	Easy to understand and debug
Safe Mapping	Avoids parameter-order mistakes
Collection Support	Supports IN queries with lists
Bean Mapping	Maps object fields directly

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Basic Setup

Spring Boot automatically configures NamedParameterJdbcTemplate if spring-boot-starter-jdbc is present.

@Autowired
private NamedParameterJdbcTemplate namedJdbcTemplate;

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Common Usage Examples

1. Insert Data Using Named Parameters

Uses named placeholders instead of ?, making SQL more readable and reducing mistakes caused by parameter order.

Stringsql="INSERT INTO users(name, email) VALUES (:name, :email)";

Map<String, Object> params =newHashMap<>();
params.put("name","Amit");
params.put("email","[email protected]");

namedJdbcTemplate.update(sql, params);

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2. Query for a Single Object

Fetches one record using named parameters, improving clarity and avoiding confusion in complex queries.

Stringsql="SELECT * FROM users WHERE id = :id";

Map<String, Object> params = Map.of("id",1L);

Useruser= namedJdbcTemplate.queryForObject(
    sql,
    params,
newBeanPropertyRowMapper<>(User.class)
);

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3. Using MapSqlParameterSource

Provides a type-safe and fluent way to pass parameters, making the code cleaner and easier to maintain than raw maps.

Stringsql="UPDATE users SET email = :email WHERE id = :id";

SqlParameterSourceparamSource=
newMapSqlParameterSource()
            .addValue("id",1L)
            .addValue("email","[email protected]");

namedJdbcTemplate.update(sql, paramSource);

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4. Using BeanPropertySqlParameterSource

Automatically maps Java object fields to SQL parameters, reducing manual coding and improving consistency.

Useruser=newUser("John","[email protected]");

Stringsql="INSERT INTO users(name, email) VALUES (:name, :email)";
namedJdbcTemplate.update(sql,newBeanPropertySqlParameterSource(user));

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5. Query with IN Clause

Handles collections safely and easily by expanding lists automatically, which is difficult and error-prone with JdbcTemplate.

Stringsql="SELECT * FROM users WHERE id IN (:ids)";

Map<String, Object> params = Map.of("ids", List.of(1,2,3));

List<User> users = namedJdbcTemplate.query(
        sql,
        params,
newBeanPropertyRowMapper<>(User.class)
);

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Difference Between JdbcTemplate and NamedParameterJdbcTemplate

Aspect	JdbcTemplate	NamedParameterJdbcTemplate
Parameter Style	Uses positional parameters (?)	Uses named parameters (:name, :id)
SQL Readability	Lower when many parameters are used	Higher and more self-explanatory
Parameter Order Dependency	Yes, parameters must be passed in correct order	No order dependency; parameters matched by name
Risk of Bugs	Higher (wrong parameter order can cause issues)	Lower (clear parameter mapping)
Code Maintainability	Harder for complex queries	Easier to maintain and modify
Learning Curve	Very easy	Easy
SQL Control	Full control over SQL	Full control over SQL
Internal Working	Direct JDBC execution	Internally uses JdbcTemplate
Performance	Very high	Almost same as JdbcTemplate (negligible difference)

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When to Use NamedParameterJdbcTemplate

Use it when:

• Queries have many parameters
• SQL readability matters
• IN clauses are common
• You want safer, cleaner SQL

Not necessary when:

• Queries are very simple
• Only 1–2 parameters are used

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Real-World Use Cases

• Complex reporting queries
• Search and filter APIs
• Dynamic SQL conditions
• Batch database operations

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Conclusion

NamedParameterJdbcTemplate makes SQL cleaner, safer, and easier to maintain by replacing positional (?) parameters with meaningful names.

It keeps all the power and performance of JdbcTemplate while greatly improving readability and reducing bugs, making it an excellent choice for real-world, complex SQL scenarios.