iron_query::SelectExpr Class Reference

Transitional representation for SELECT query. More...

#include <select_expr.hpp>

Inheritance diagram for iron_query::SelectExpr:

Collaboration diagram for iron_query::SelectExpr:

Public Member Functions
	SelectExpr (const VirtualTable &tbl)
	Starts a SELECT ... FROM tbl query. tbl may be a table, a join, or anything VirtualTable::As has aliased.
SelectExpr	Distinct () &&
	Adds DISTINCT to the SELECT list, eliminating duplicate rows.
SelectExpr	DistinctOn (Expr exp) &&
	Sets DISTINCT ON to a single expression. Mutually exclusive with Distinct.
SelectExpr	DistinctOn (std::initializer_list< Expr > exps) &&
	Sets DISTINCT ON to a comma-separated list of expressions. Mutually exclusive with Distinct.
SelectExpr	Select (SelectItem item) &&
	Sets the SELECT list to a single entry.
SelectExpr	Select (std::initializer_list< SelectItem > items) &&
	Sets the SELECT list to a comma-separated list of entries.
SelectExpr	Where (Condition exp) &&
	Sets the WHERE clause.
SelectExpr	OrderBy (OrderByTerm term) &&
	Sets the ORDER BY clause to a single term.
SelectExpr	OrderBy (std::initializer_list< OrderByTerm > terms) &&
	Sets the ORDER BY clause to a comma-separated list of terms.
SelectExpr	GroupBy (Expr exp) &&
	Sets the GROUP BY clause to a single expression.
SelectExpr	GroupBy (std::initializer_list< Expr > exps) &&
	Sets the GROUP BY clause to a comma-separated list of expressions.
SelectExpr	Having (Condition exp) &&
	Sets the HAVING clause.
SelectExpr	Limit (int limit) &&
	Sets the LIMIT clause.
SelectExpr	Offset (int offset) &&
	Sets the OFFSET clause.
std::string	ToString () const override
std::string	ToStringFormatted () const override
	Renders the query with each clause on its own line, indented, e.g.:
Public Member Functions inherited from iron_query::VirtualTable
virtual std::string	ToStringBracketed () const
	Renders this table value as SQL text, parenthesized so it can be safely embedded as a subquery. Overridden by Table to skip bracketing, since a bare table name never needs it.
virtual std::string	ToStringAsFromItem () const
	Renders this table value as a FROM item. Distinct from ToStringBracketed because PostgreSQL's table_ref grammar accepts a bare join but parenthesizes one only when an alias follows.
Table	As (std::string_view name) const
	Aliases this table value as this AS name, usable as a FROM source. name must be a valid (optionally dotted) SQL identifier.
	operator Expr () const &&
	Converts this table value into a subquery expression, e.g. for use as a scalar subquery. Only available on rvalues.

Detailed Description

Transitional representation for SELECT query.

See also

https://www.postgresql.org/docs/current/sql-select.html

Constructor & Destructor Documentation

SelectExpr()

iron_query::SelectExpr::SelectExpr

(

const VirtualTable &

tbl

)

Starts a SELECT ... FROM tbl query. tbl may be a table, a join, or anything VirtualTable::As has aliased.

Exceptions

LogicError

if tbl is a subquery without an alias.

Member Function Documentation

DistinctOn() [1/2]

SelectExpr iron_query::SelectExpr::DistinctOn

(

Expr

exp

)

&&

Sets DISTINCT ON to a single expression. Mutually exclusive with Distinct.

Exceptions

LogicError

if DISTINCT ON was already set.

DistinctOn() [2/2]

SelectExpr iron_query::SelectExpr::DistinctOn

(

std::initializer_list< Expr >

exps

)

&&

Sets DISTINCT ON to a comma-separated list of expressions. Mutually exclusive with Distinct.

Note

Does not check that the leftmost ORDER BY expressions match these, which PostgreSQL requires.

Exceptions

LogicError

if DISTINCT ON was already set.

GroupBy() [1/2]

SelectExpr iron_query::SelectExpr::GroupBy

(

Expr

exp

)

&&

Sets the GROUP BY clause to a single expression.

Note

Does not check that non-aggregated Select items are covered by the GROUP BY expressions.

Exceptions

LogicError

if the GROUP BY clause was already set.

GroupBy() [2/2]

SelectExpr iron_query::SelectExpr::GroupBy

(

std::initializer_list< Expr >

exps

)

&&

Sets the GROUP BY clause to a comma-separated list of expressions.

Note

Does not check that non-aggregated Select items are covered by the GROUP BY expressions.

Exceptions

LogicError

if the GROUP BY clause was already set.

Having()

SelectExpr iron_query::SelectExpr::Having

(

Condition

exp

)

&&

Sets the HAVING clause.

Note

Does not check that exp references only grouped columns or aggregates.

Exceptions

LogicError

if the HAVING clause was already set.

Limit()

SelectExpr iron_query::SelectExpr::Limit

(

int

limit

)

&&

Sets the LIMIT clause.

Exceptions

LogicError

if the LIMIT clause was already set.

Offset()

SelectExpr iron_query::SelectExpr::Offset

(

int

offset

)

&&

Sets the OFFSET clause.

Exceptions

LogicError

if the OFFSET clause was already set.

OrderBy() [1/2]

SelectExpr iron_query::SelectExpr::OrderBy

(

OrderByTerm

term

)

&&

Sets the ORDER BY clause to a single term.

Exceptions

LogicError

if the ORDER BY clause was already set.

OrderBy() [2/2]

SelectExpr iron_query::SelectExpr::OrderBy

(

std::initializer_list< OrderByTerm >

terms

)

&&

Sets the ORDER BY clause to a comma-separated list of terms.

Exceptions

LogicError

if the ORDER BY clause was already set.

Select() [1/2]

SelectExpr iron_query::SelectExpr::Select

(

SelectItem

item

)

&&

Sets the SELECT list to a single entry.

Exceptions

LogicError

if the SELECT list was already set.

Select() [2/2]

SelectExpr iron_query::SelectExpr::Select

(

std::initializer_list< SelectItem >

items

)

&&

Sets the SELECT list to a comma-separated list of entries.

Exceptions

LogicError

if the SELECT list was already set.

ToString()

std::string iron_query::SelectExpr::ToString ( ) const

overridevirtual

Exceptions

LogicError

if the SELECT or FROM clause was not set, or if both Distinct and DistinctOn were set.

Implements iron_query::VirtualTable.

ToStringFormatted()

std::string iron_query::SelectExpr::ToStringFormatted ( ) const

overridevirtual

Renders the query with each clause on its own line, indented, e.g.:

SELECT
    a,
    b
FROM
    users
WHERE
    a > b

Exceptions

LogicError

if the SELECT or FROM clause was not set.

Reimplemented from iron_query::VirtualTable.

Where()

SelectExpr iron_query::SelectExpr::Where

(

Condition

exp

)

&&

Sets the WHERE clause.

Exceptions

LogicError

if the WHERE clause was already set.

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The documentation for this class was generated from the following file:

• include/iron_query/select_expr.hpp