TypedSqlBuilder Examples

This document demonstrates various TypedSqlBuilder queries and their corresponding SQL Server output.

Table Definitions

For these examples, we use the following table structure:

public class Customer() : SqlTable("customers")
{
    [Column("Id")] public SqlIntColumn Id { get; set; } = default!;
    [Column("Age")] public SqlIntColumn Age { get; set; } = default!;
    [Column("Name")] public SqlStringColumn Name { get; set; } = default!;
    [Column("IsActive")] public SqlBoolColumn IsActive { get; set; } = default!;
}

public class Product() : SqlTable("products") 
{
    [Column("Id")] public SqlIntColumn Id { get; set; } = default!;
    [Column("ProductName")] public SqlStringColumn ProductName { get; set; } = default!;
    [Column("Price")] public SqlDecimalColumn Price { get; set; } = default!;
    [Column("CreatedDate")] public SqlDateTimeColumn CreatedDate { get; set; } = default!;
    [Column("UniqueId")] public SqlGuidColumn UniqueId { get; set; } = default!;
}

public class Order() : SqlTable("orders")
{
    [Column("Id")] public SqlIntColumn Id { get; set; } = default!;
    [Column("CustomerId")] public SqlIntColumn CustomerId { get; set; } = default!;
    [Column("ProductId")] public SqlIntColumn ProductId { get; set; } = default!;
    [Column("Amount")] public SqlIntColumn Amount { get; set; } = default!;
}

public static class Db
{
    public static Customer Customers { get; } = new();
    public static Product Products { get; } = new();
    public static Order Orders { get; } = new();
}

Basic Queries

Simple SELECT All Columns

C# Code:

Db.Customers.From()

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]

SELECT Specific Columns

C# Code:

Db.Customers.From()
    .Select(c => (c.Id, c.Name))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name]
FROM
    [customers] [a0]

Data Modification Operations

INSERT Statement

C# Code:

Db.Customers.Insert()
    .Value(c => c.Id, 1)
    .Value(c => c.Name, "John Doe")
    .Value(c => c.Age, 30)
    .Value(c => c.IsActive, true)

Generated SQL:

INSERT INTO [customers] ([Id], [Name], [Age], [IsActive])
VALUES (@p0, @p1, @p2, @p3)

UPDATE Statement

C# Code:

Db.Customers.Update()
    .Set(c => c.Name, "Jane Smith")
    .Set(c => c.Age, 32)
    .Set(c => c.IsActive, false)
    .Where(c => c.Id == 1)

Generated SQL:

UPDATE [customers] 
SET [Name] = @p0, [Age] = @p1, [IsActive] = @p2
WHERE [Id] = @p3

DELETE Statement

C# Code:

Db.Customers.Delete()
    .Where(c => c.Id == 1)

Generated SQL:

DELETE FROM [customers]
WHERE [Id] = @p0

WHERE Clauses

Simple WHERE Condition

C# Code:

Db.Customers.From()
    .Where(c => c.Age > 18)

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
WHERE
    [a0].[Age] > @p0

Multiple WHERE Conditions (AND)

C# Code:

Db.Customers.From()
    .Where(c => c.Age > 18 && c.Name != "Admin")

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
WHERE
    [a0].[Age] > @p0 AND [a0].[Name] <> @p1

Complex WHERE with OR Logic

C# Code:

Db.Customers.From()
    .Where(c => (c.Age > 18 && c.Age < 65) ||
                c.Name == "VIP")

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
WHERE
    ([a0].[Age] > @p0 AND [a0].[Age] < @p1) OR
    [a0].[Name] = @p2

ORDER BY Clauses

Simple ORDER BY

C# Code:

Db.Customers.From()
    .OrderBy(c => (c.Name, Sort.Asc))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
ORDER BY
    [a0].[Name] ASC

Multiple ORDER BY Columns

C# Code:

Db.Customers.From()
    .OrderBy(c => ((c.Name, Sort.Asc),
                   (c.Age, Sort.Desc)))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
ORDER BY
    [a0].[Name] ASC, [a0].[Age] DESC

Complex Queries with Multiple Clauses

WHERE + ORDER BY + SELECT

C# Code:

Db.Customers.From()
    .Where(c => c.Age > 18)
    .OrderBy(c => (c.Name, Sort.Asc))
    .Select(c => (c.Id + 1, c.Name + "!"))

Generated SQL:

SELECT
    ([a0].[Id] + @p0) AS [Proj0],
    ([a0].[Name] + @p1) AS [Proj1]
FROM
    [customers] [a0]
WHERE
    [a0].[Age] > @p2
ORDER BY
    [a0].[Name] ASC

Named Projections

Named Tuple Projections

C# Code:

Db.Customers.From()
    .Where(c => c.Age >= 21)
    .Select(c => (
        CustomerId: c.Id,
        CustomerInfo: c.Name + " (Customer)",
        AdjustedAge: c.Age + 5
    ))

Generated SQL:

SELECT
    [a0].[Id] AS [CustomerId],
    ([a0].[Name] + @p0) AS [CustomerInfo],
    ([a0].[Age] + @p1) AS [AdjustedAge]
FROM
    [customers] [a0]
WHERE
    [a0].[Age] >= @p2

INNER JOIN

Basic INNER JOIN

C# Code:

Db.Customers.From()
    .InnerJoin(Db.Orders, 
               c => c.Id, 
               o => o.CustomerId,
               (customer, order) => (Customer: customer, Order: order))
    .Select(result => (result.Customer.Id, result.Customer.Name, result.Order.Id, result.Order.Amount))

Generated SQL:

SELECT
    [a0].[Id] AS [CustomerId],
    [a0].[Name] AS [Name],
    [a1].[Id] AS [OrderId],
    [a1].[Amount] AS [Amount]
FROM
    [customers] [a0]
INNER JOIN [orders] [a1] ON [a0].[Id] = [a1].[CustomerId]

INNER JOIN with Named Projections

C# Code:

Db.Customers.From()
    .InnerJoin(Db.Orders,
               c => c.Id,
               o => o.CustomerId,
               (customer, order) => (Customer: customer, Order: order))
    .Select(result => (
        result.Customer.Name,
        result.Order.Amount
    ))

Generated SQL:

SELECT
    [a0].[Name] AS [Name],
    [a1].[Amount] AS [Amount]
FROM
    [customers] [a0]
INNER JOIN [orders] [a1] ON [a0].[Id] = [a1].[CustomerId]

INNER JOIN with WHERE

Complex JOIN with Multiple WHERE Conditions

C# Code:

Db.Customers.From()
    .Where(c => c.Age >= 18)
    .InnerJoin(Db.Orders,
               c => c.Id,
               o => o.CustomerId,
               (customer, order) => (Customer: customer, Order: order))    
    .Where(result => result.Order.Amount > 100)
    .Select(result => (result.Customer.Id, result.Customer.Name, result.Customer.Age,
                       result.Order.Id, result.Order.Amount))

Generated SQL:

SELECT
    [a1].[Id] AS [CustomerId],
    [a1].[Name] AS [Name],
    [a1].[Age] AS [Age],
    [a2].[Id] AS [OrderId],
    [a2].[Amount] AS [Amount]
FROM
    (SELECT
        [a0].[Id] AS [Id],
        [a0].[Age] AS [Age],
        [a0].[Name] AS [Name],
        [a0].[IsActive] AS [IsActive]
    FROM
        [customers] [a0]
    WHERE
        [a0].[Age] >= @p0) [a1]
INNER JOIN [orders] [a2] ON [a1].[Id] = [a2].[CustomerId]
WHERE
    [a2].[Amount] > @p1

LEFT JOIN

Basic LEFT JOIN

C# Code:

Db.Customers.From()
    .LeftJoin(Db.Orders,
              c => c.Id,
              o => o.CustomerId,
              (customer, order) => (Customer: customer, Order: order))
    .Select(result => (result.Customer.Id, result.Customer.Name, result.Order.Id, result.Order.Amount))

Generated SQL:

SELECT
    [a0].[Id] AS [CustomerId],
    [a0].[Name] AS [Name],
    [a1].[Id] AS [OrderId],
    [a1].[Amount] AS [Amount]
FROM
    [customers] [a0]
LEFT JOIN [orders] [a1] ON [a0].[Id] = [a1].[CustomerId]

GROUP BY with Aggregates

Simple GROUP BY with COUNT

C# Code:

Db.Customers.From()
    .GroupBy(c => c.Age)
    .Select((c, agg) => (
        Age: c.Age,
        Count: agg.Count()
    ))

Generated SQL:

SELECT
    [a0].[Age] AS [Age],
    COUNT(*) AS [Count]
FROM
    [customers] [a0]
GROUP BY
    [a0].[Age]

Complex GROUP BY with JOIN and SUM

C# Code:

Db.Customers.From()
    .InnerJoin(Db.Orders,
               c => c.Id,
               o => o.CustomerId,
               (customer, order) => (Customer: customer, Order: order))    
    .GroupBy(result => (result.Customer.Id, result.Customer.Name))
    .Select((result, agg) => (
        CustomerId: result.Customer.Id,
        CustomerName: result.Customer.Name,
        TotalAmount: agg.Sum(result.Order.Amount)
    ))

Generated SQL:

SELECT
    [a0].[Id] AS [CustomerId],
    [a0].[Name] AS [CustomerName],
    SUM([a1].[Amount]) AS [TotalAmount]
FROM
    [customers] [a0]
INNER JOIN [orders] [a1] ON [a0].[Id] = [a1].[CustomerId]
GROUP BY
    [a0].[Id], [a0].[Name]

GROUP BY with HAVING

GROUP BY with HAVING Clause

C# Code:

Db.Customers.From()
    .GroupBy(c => c.Age)
    .Having((c, agg) => agg.Count() > 1)
    .Select((c, agg) => (
        Age: c.Age,
        Count: agg.Count()
    ))

Generated SQL:

SELECT
    [a0].[Age] AS [Age],
    COUNT(*) AS [Count]
FROM
    [customers] [a0]
GROUP BY
    [a0].[Age]
HAVING
    COUNT(*) > @p0

Scalar Queries (Aggregates)

Simple COUNT

C# Code:

Db.Customers.From().Count()

Generated SQL:

SELECT
    COUNT(*) AS [Proj0]
FROM
    [customers] [a0]

COUNT with WHERE

C# Code:

Db.Customers.From()
    .Where(c => c.Age >= 18)
    .Count()

Generated SQL:

SELECT
    COUNT(*) AS [Proj0]
FROM
    [customers] [a0]
WHERE
    [a0].[Age] >= @p0

SUM

C# Code:

Db.Products.From()
    .Select(p => p.Price)
    .Sum()

Generated SQL:

SELECT
    SUM([a0].[Price]) AS [Proj0]
FROM
    [products] [a0]

AVG

C# Code:

Db.Products.From()
    .Select(p => p.Price)
    .Avg()

Generated SQL:

SELECT
    AVG([a0].[Price]) AS [Proj0]
FROM
    [products] [a0]

MIN

C# Code:

Db.Products.From()
    .Select(p => p.Price)
    .Min()

Generated SQL:

SELECT
    MIN([a0].[Price]) AS [Proj0]
FROM
    [products] [a0]

MAX

C# Code:

Db.Products.From()
    .Select(p => p.Price)
    .Max()

Generated SQL:

SELECT
    MAX([a0].[Price]) AS [Proj0]
FROM
    [products] [a0]

AVG with WHERE

C# Code:

Db.Products.From()
    .Where(p => p.Price > 100m)
    .Select(p => p.Price)
    .Avg()

Generated SQL:

SELECT
    AVG([a0].[Price]) AS [Proj0]
FROM
    [products] [a0]
WHERE
    [a0].[Price] > @p0

Built-in Functions

Mathematical Functions

ABS Function

C# Code:

Db.Customers.From()
    .Select(c => (c.Id, c.Age.Abs()))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    ABS([a0].[Age]) AS [Proj0]
FROM
    [customers] [a0]

ABS with Expression

C# Code:

Db.Customers.From()
    .Select(c => (c.Id, (c.Age - 50).Abs()))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    ABS([a0].[Age] - @p0) AS [Proj0]
FROM
    [customers] [a0]

ABS in WHERE Clause

C# Code:

Db.Customers.From()
    .Where(c => c.Age.Abs() > 30)
    .Select(c => (c.Id, c.Name, c.Age))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name],
    [a0].[Age] AS [Age]
FROM
    [customers] [a0]
WHERE
    ABS([a0].[Age]) > @p0

String Functions (LIKE)

LIKE with Wildcard

C# Code:

Db.Customers.From()
    .Where(c => c.Name.Like("Jo%"))
    .Select(c => (c.Id, c.Name))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name]
FROM
    [customers] [a0]
WHERE
    [a0].[Name] LIKE @p0

LIKE with Single Character Wildcard

C# Code:

Db.Customers.From()
    .Where(c => c.Name.Like("J_n"))
    .Select(c => (c.Id, c.Name))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name]
FROM
    [customers] [a0]
WHERE
    [a0].[Name] LIKE @p0

LIKE with Multiple Wildcards

C# Code:

Db.Customers.From()
    .Where(c => c.Name.Like("%o_n%"))
    .Select(c => (c.Id, c.Name))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name]
FROM
    [customers] [a0]
WHERE
    [a0].[Name] LIKE @p0

Date Functions

AddDays

C# Code:

Db.Products.From()
    .Select(p => p.CreatedDate.AddDays(30))

Generated SQL:

SELECT
    DATEADD(day, @p0, [a0].[CreatedDate]) AS [Proj0]
FROM
    [products] [a0]

AddMonths

C# Code:

Db.Products.From()
    .Select(p => p.CreatedDate.AddMonths(6))

Generated SQL:

SELECT
    DATEADD(month, @p0, [a0].[CreatedDate]) AS [Proj0]
FROM
    [products] [a0]

AddYears

C# Code:

Db.Products.From()
    .Select(p => p.CreatedDate.AddYears(1))

Generated SQL:

SELECT
    DATEADD(year, @p0, [a0].[CreatedDate]) AS [Proj0]
FROM
    [products] [a0]

Day Function

C# Code:

Db.Products.From()
    .Select(p => p.CreatedDate.Day())

Generated SQL:

SELECT
    DAY([a0].[CreatedDate]) AS [Proj0]
FROM
    [products] [a0]

NULL Checks

IS NULL

C# Code:

Db.Customers.From()
    .Where(c => c.Name == SqlNull.Value)

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
WHERE
    [a0].[Name] IS NULL

IS NOT NULL

C# Code:

Db.Customers.From()
    .Where(c => c.Name != SqlNull.Value)

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
WHERE
    [a0].[Name] IS NOT NULL

IN Clauses

IN with Literal Values

C# Code:

Db.Customers.From()
    .Where(c => c.Age.In(18, 21, 25, 30))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
WHERE
    [a0].[Age] IN (@p0, @p1, @p2, @p3)

Subqueries

IN with Subquery

C# Code:

Db.Customers.From()
    .Where(c => c.Age.In(
        Db.Customers.From()
            .Where(x => x.Name == "VIP")
            .Select(x => x.Age)
    ))

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
WHERE
    [a0].[Age] IN (
        SELECT
            [a1].[Age] AS [Age]
        FROM
            [customers] [a1]
        WHERE
            [a1].[Name] = @p0)

Parameters

TypedSqlBuilder automatically parameterizes literal values to prevent SQL injection and improve query plan reuse. You can also explicitly define parameters:

Named Parameters

C# Code:

Db.Products.From()
    .Where(p => p.Price > "minPrice".AsDecimalParam())

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[ProductName] AS [ProductName],
    [a0].[Price] AS [Price],
    [a0].[CreatedDate] AS [CreatedDate],
    [a0].[UniqueId] AS [UniqueId]
FROM
    [products] [a0]
WHERE
    [a0].[Price] > @minPrice

Named Parameters with Functions

C# Code:

Db.Customers.From()
    .Where(c => c.Age.Abs() > 
                "minAge".AsIntParam().Abs())

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name],
    [a0].[Age] AS [Age]
FROM
    [customers] [a0]
WHERE
    ABS([a0].[Age]) > ABS(@minAge)

DISTINCT Operations

DISTINCT Example

C# Code:

Db.Customers.From()
    .Select(c => c.Age)
    .Distinct()

Generated SQL:

SELECT DISTINCT
    [a0].[Age] AS [Age]
FROM
    [customers] [a0]

LIMIT Operations

LIMIT Example (Limit Only)

C# Code:

Db.Customers.From()
    .Limit(5)

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
ORDER BY
    [a0].[Id] ASC
OFFSET 0 ROWS
FETCH NEXT 5 ROWS ONLY

LIMIT with OFFSET Example (Pagination)

C# Code:

Db.Customers.From()
    .OrderBy(c => (c.Id, Sort.Asc))
    .Limit(10, 20)

Generated SQL:

SELECT
    [a0].[Id] AS [Id],
    [a0].[Age] AS [Age],
    [a0].[Name] AS [Name],
    [a0].[IsActive] AS [IsActive]
FROM
    [customers] [a0]
ORDER BY
    [a0].[Id] ASC
OFFSET 20 ROWS
FETCH NEXT 10 ROWS ONLY

Combining DISTINCT and LIMIT

DISTINCT with LIMIT Example

C# Code:

Db.Customers.From()
    .Select(c => c.Age)
    .Distinct()
    .Limit(10)

Generated SQL:

SELECT DISTINCT
    [a0].[Age] AS [Age]
FROM
    [customers] [a0]
ORDER BY
    [a0].[Age] ASC
OFFSET 0 ROWS
FETCH NEXT 10 ROWS ONLY

Set Operations

TypedSqlBuilder supports SQL set operations to combine results from multiple queries.

UNION

UNION combines the result sets of two SELECT statements, removing duplicates.

C# Code:

Db.Customers.From()
    .Where(c => c.Age > 30)
    .Select(c => (c.Id, c.Name))
    .Union(
        Db.Customers.From()
            .Where(c => c.Name == "Alice")
            .Select(c => (c.Id, c.Name))
    )

Generated SQL:

SELECT 
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name]
FROM 
    [customers] [a0]
WHERE 
    [a0].[Age] > @p0
UNION
SELECT 
    [a1].[Id] AS [Id],
    [a1].[Name] AS [Name]
FROM 
    [customers] [a1]
WHERE 
    [a1].[Name] = @p1

INTERSECT

INTERSECT returns the common records from two SELECT statements.

C# Code:

Db.Customers.From()
    .Where(c => c.Age > 25)
    .Select(c => (c.Id, c.Name))
    .Intersect(
        Db.Customers.From()
            .Where(c => c.Name == "John")
            .Select(c => (c.Id, c.Name))
    )

Generated SQL:

SELECT 
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name]
FROM 
    [customers] [a0]
WHERE 
    [a0].[Age] > @p0
INTERSECT
SELECT 
    [a1].[Id] AS [Id],
    [a1].[Name] AS [Name]
FROM 
    [customers] [a1]
WHERE 
    [a1].[Name] = @p1

EXCEPT

EXCEPT returns records from the first SELECT statement that are not found in the second.

C# Code:

Db.Customers.From()
    .Select(c => (c.Id, c.Name))
    .Except(
        Db.Customers.From()
            .Where(c => c.Age < 18)
            .Select(c => (c.Id, c.Name))
    )

Generated SQL:

SELECT 
    [a0].[Id] AS [Id],
    [a0].[Name] AS [Name]
FROM 
    [customers] [a0]
EXCEPT
SELECT 
    [a1].[Id] AS [Id],
    [a1].[Name] AS [Name]
FROM 
    [customers] [a1]
WHERE 
    [a1].[Age] < @p0

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TypedSqlBuilder Examples

Table Definitions

Basic Queries

Simple SELECT All Columns

SELECT Specific Columns

Data Modification Operations

INSERT Statement

UPDATE Statement

DELETE Statement

WHERE Clauses

Simple WHERE Condition

Multiple WHERE Conditions (AND)

Complex WHERE with OR Logic

ORDER BY Clauses

Simple ORDER BY

Multiple ORDER BY Columns

Complex Queries with Multiple Clauses

WHERE + ORDER BY + SELECT

Named Projections

Named Tuple Projections

INNER JOIN

Basic INNER JOIN

INNER JOIN with Named Projections

INNER JOIN with WHERE

Complex JOIN with Multiple WHERE Conditions

LEFT JOIN

Basic LEFT JOIN

GROUP BY with Aggregates

Simple GROUP BY with COUNT

Complex GROUP BY with JOIN and SUM

GROUP BY with HAVING

GROUP BY with HAVING Clause

Scalar Queries (Aggregates)

Simple COUNT

COUNT with WHERE

SUM

AVG

MIN

MAX

AVG with WHERE

Built-in Functions

Mathematical Functions

ABS Function

ABS with Expression

ABS in WHERE Clause

String Functions (LIKE)

LIKE with Wildcard

LIKE with Single Character Wildcard

LIKE with Multiple Wildcards

Date Functions

AddDays

AddMonths

AddYears

Day Function

NULL Checks

IS NULL

IS NOT NULL

IN Clauses

IN with Literal Values

Subqueries

IN with Subquery

Parameters

Named Parameters

Named Parameters with Functions

DISTINCT Operations

DISTINCT Example

LIMIT Operations

LIMIT Example (Limit Only)

LIMIT with OFFSET Example (Pagination)

Combining DISTINCT and LIMIT

DISTINCT with LIMIT Example

Set Operations

UNION

INTERSECT