# Testing queries from documentation (CRUD):

Schema:
pony.orm.examples.estore

>>> Product.get(id=1)

SELECT "id", "name", "description", "picture", "price", "quantity"
FROM "Product"
WHERE "id" = ?

>>> Product.get(name="Product1")

SELECT "id", "name", "description", "picture", "price", "quantity"
FROM "Product"
WHERE "name" = ?
LIMIT 2

>>> Product.select(lambda p: p.price > 100)

SELECT "p"."id", "p"."name", "p"."description", "p"."picture", "p"."price", "p"."quantity"
FROM "Product" "p"
WHERE "p"."price" > 100

>>> x = 100
>>> Product.select(lambda p: p.price > x)

SELECT "p"."id", "p"."name", "p"."description", "p"."picture", "p"."price", "p"."quantity"
FROM "Product" "p"
WHERE "p"."price" > ?

>>> Product.select(lambda p: p.price > 100).order_by(lambda p: desc(p.price))

SELECT "p"."id", "p"."name", "p"."description", "p"."picture", "p"."price", "p"."quantity"
FROM "Product" "p"
WHERE "p"."price" > 100
ORDER BY "p"."price" DESC

>>> Product.select(lambda p: p.price > 100).order_by(desc(Product.price))

SELECT "p"."id", "p"."name", "p"."description", "p"."picture", "p"."price", "p"."quantity"
FROM "Product" "p"
WHERE "p"."price" > 100
ORDER BY "p"."price" DESC

>>> Product.select(lambda p: p.price > 100).order_by(desc(Product.price), Product.name)

SELECT "p"."id", "p"."name", "p"."description", "p"."picture", "p"."price", "p"."quantity"
FROM "Product" "p"
WHERE "p"."price" > 100
ORDER BY "p"."price" DESC, "p"."name"

>>> Product.select(lambda p: p.price > 100).order_by("desc(p.price), p.name")

SELECT "p"."id", "p"."name", "p"."description", "p"."picture", "p"."price", "p"."quantity"
FROM "Product" "p"
WHERE "p"."price" > 100
ORDER BY "p"."price" DESC, "p"."name"

>>> Product.select().order_by(lambda p: desc(p.price))[:10]

SELECT "p"."id", "p"."name", "p"."description", "p"."picture", "p"."price", "p"."quantity"
FROM "Product" "p"
ORDER BY "p"."price" DESC
LIMIT 10


# Testing declarative queries from documentation:

# TODO

# Testing aggregation queries from documentation:

Schema:
pony.orm.examples.university1

>>> sum(s.gpa for s in Student if s.group.number == 101)

SELECT coalesce(SUM("s"."gpa"), 0)
FROM "Student" "s"
WHERE "s"."group" = 101

>>> count(s for s in Student if s.gpa > 3)

SELECT COUNT(*)
FROM "Student" "s"
WHERE "s"."gpa" > 3


>>> min(s.name for s in Student if "Philosophy" in s.courses.name)

SELECT MIN("s"."name")
FROM "Student" "s"
WHERE 'Philosophy' IN (
    SELECT "t-1"."course_name"
    FROM "Course_Student" "t-1"
    WHERE "s"."id" = "t-1"."student"
    )

>>> max(s.dob for s in Student if s.group.number == 101)

SELECT MAX("s"."dob")
FROM "Student" "s"
WHERE "s"."group" = 101

>>> avg(s.gpa for s in Student if s.group.dept.number == 44)

SELECT AVG("s"."gpa")
FROM "Student" "s", "Group" "group"
WHERE "group"."dept" = 44
  AND "s"."group" = "group"."number"

>>> select(s for s in Student if s.group.number == 101 and s.dob == max(s.dob for s in Student if s.group.number == 101))

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
WHERE "s"."group" = 101
  AND "s"."dob" = (
    SELECT MAX("s-2"."dob")
    FROM "Student" "s-2"
    WHERE "s-2"."group" = 101
    )

>>> select(g for g in Group if avg(s.gpa for s in g.students) > 4.5)

SELECT "g"."number", "g"."major", "g"."dept"
FROM "Group" "g"
WHERE (
    SELECT AVG("s"."gpa")
    FROM "Student" "s"
    WHERE "g"."number" = "s"."group"
    ) > 4.5

>>> select(g for g in Group if avg(g.students.gpa) > 4.5)

SELECT "g"."number"
FROM "Group" "g"
  LEFT JOIN "Student" "student"
    ON "g"."number" = "student"."group"
GROUP BY "g"."number"
HAVING AVG("student"."gpa") > 4.5

>>> select((s.group, min(s.gpa), max(s.gpa)) for s in Student)

SELECT "s"."group", MIN("s"."gpa"), MAX("s"."gpa")
FROM "Student" "s"
GROUP BY "s"."group"

>>> select((g, min(g.students.gpa), max(g.students.gpa)) for g in Group)

SELECT "g"."number", MIN("student"."gpa"), MAX("student"."gpa")
FROM "Group" "g"
  LEFT JOIN "Student" "student"
    ON "g"."number" = "student"."group"
GROUP BY "g"."number"

>>> select((g, g.students.name, min(g.students.gpa), max(g.students.gpa)) for g in Group)

SELECT "g"."number", "student"."name", MIN("student"."gpa"), MAX("student"."gpa")
FROM "Group" "g"
  LEFT JOIN "Student" "student"
    ON "g"."number" = "student"."group"
GROUP BY "g"."number", "student"."name"

>>> count(s for s in Student if s.group.number == 101)

SELECT COUNT(*)
FROM "Student" "s"
WHERE "s"."group" = 101

>>> select((g, count(g.students)) for g in Group if g.dept.number == 44)

SELECT "g"."number", COUNT(DISTINCT "student"."id")
FROM "Group" "g"
  LEFT JOIN "Student" "student"
    ON "g"."number" = "student"."group"
WHERE "g"."dept" = 44
GROUP BY "g"."number"

>>> select((s.group, count(s)) for s in Student if s.group.dept.number == 44)

SELECT "s"."group", COUNT(DISTINCT "s"."id")
FROM "Student" "s", "Group" "group"
WHERE "group"."dept" = 44
  AND "s"."group" = "group"."number"
GROUP BY "s"."group"

>>> select((g, count(s for s in g.students if s.gpa <= 3), count(s for s in g.students if s.gpa > 3 and s.gpa <= 4), count(s for s in g.students if s.gpa > 4)) for g in Group)

SELECT "g"."number", (
    SELECT COUNT(DISTINCT "s"."id")
    FROM "Student" "s"
    WHERE "g"."number" = "s"."group"
      AND "s"."gpa" <= 3
    ), (
    SELECT COUNT(DISTINCT "s"."id")
    FROM "Student" "s"
    WHERE "g"."number" = "s"."group"
      AND "s"."gpa" > 3
      AND "s"."gpa" <= 4
    ), (
    SELECT COUNT(DISTINCT "s"."id")
    FROM "Student" "s"
    WHERE "g"."number" = "s"."group"
      AND "s"."gpa" > 4
    )
FROM "Group" "g"

>>> select((s.group, count(s.gpa <= 3), count(s.gpa > 3 and s.gpa <= 4), count(s.gpa > 4)) for s in Student)

SELECT "s"."group", COUNT(case when "s"."gpa" <= 3 then 1 else null end), COUNT(case when "s"."gpa" > 3 AND "s"."gpa" <= 4 then 1 else null end), COUNT(case when "s"."gpa" > 4 then 1 else null end)
FROM "Student" "s"
GROUP BY "s"."group"

>>> left_join((g, count(s.gpa <= 3), count(s.gpa > 3 and s.gpa <= 4), count(s.gpa > 4)) for g in Group for s in g.students)

SELECT "g"."number", COUNT(case when "s"."gpa" <= 3 then 1 else null end), COUNT(case when "s"."gpa" > 3 AND "s"."gpa" <= 4 then 1 else null end), COUNT(case when "s"."gpa" > 4 then 1 else null end)
FROM "Group" "g"
  LEFT JOIN "Student" "s"
    ON "g"."number" = "s"."group"
GROUP BY "g"."number"

>>> select((s.dob.year, avg(s.gpa)) for s in Student)

SELECT cast(substr("s"."dob", 1, 4) as integer), AVG("s"."gpa")
FROM "Student" "s"
GROUP BY cast(substr("s"."dob", 1, 4) as integer)

Schema:
pony.orm.examples.estore

>>> select((item.order, sum(item.price * item.quantity)) for item in OrderItem if item.order.id == 123)

SELECT "item"."order", coalesce(SUM(("item"."price" * "item"."quantity")), 0)
FROM "OrderItem" "item"
WHERE "item"."order" = 123
GROUP BY "item"."order"

>>> select((order, sum(order.items.price * order.items.quantity)) for order in Order if order.id == 123)

SELECT "order"."id", coalesce(SUM(("orderitem"."price" * "orderitem"."quantity")), 0)
FROM "Order" "order"
  LEFT JOIN "OrderItem" "orderitem"
    ON "order"."id" = "orderitem"."order"
WHERE "order"."id" = 123
GROUP BY "order"."id"

>>> select((item.order, item.order.total_price, sum(item.price * item.quantity)) for item in OrderItem if item.order.total_price < sum(item.price * item.quantity))

SELECT "item"."order", "order"."total_price", coalesce(SUM(("item"."price" * "item"."quantity")), 0)
FROM "OrderItem" "item", "Order" "order"
WHERE "item"."order" = "order"."id"
GROUP BY "item"."order", "order"."total_price"
HAVING "order"."total_price" < coalesce(SUM(("item"."price" * "item"."quantity")), 0)

>>> select(c for c in Customer for p in c.orders.items.product if 'Tablets' in p.categories.name and count(p) > 1)

SELECT DISTINCT "c"."id"
FROM "Customer" "c", "Order" "order", "OrderItem" "orderitem"
WHERE 'Tablets' IN (
    SELECT "category"."name"
    FROM "Category_Product" "t-1", "Category" "category"
    WHERE "orderitem"."product" = "t-1"."product"
      AND "t-1"."category" = "category"."id"
    )
  AND "c"."id" = "order"."customer"
  AND "order"."id" = "orderitem"."order"
GROUP BY "c"."id"
HAVING COUNT(DISTINCT "orderitem"."product") > 1

Schema:
pony.orm.examples.university1

>>> select((s.group, count(s)) for s in Student  if s.group.dept.number == 44 and avg(s.gpa) > 4)

SELECT "s"."group", COUNT(DISTINCT "s"."id")
FROM "Student" "s", "Group" "group"
WHERE "group"."dept" = 44
  AND "s"."group" = "group"."number"
GROUP BY "s"."group"
HAVING AVG("s"."gpa") > 4

>>> select(g for g in Group if max(g.students.gpa) < 4)

SELECT "g"."number"
FROM "Group" "g"
  LEFT JOIN "Student" "student"
    ON "g"."number" = "student"."group"
GROUP BY "g"."number"
HAVING MAX("student"."gpa") < 4

>>> select(g for g in Group if JOIN(max(g.students.gpa) < 4))

SELECT "g"."number"
FROM "Group" "g"
  LEFT JOIN (
    SELECT "student"."group" AS "group", MAX("student"."gpa") AS "expr-1"
    FROM "Student" "student"
    GROUP BY "student"."group"
    ) "t-1"
    ON "g"."number" = "t-1"."group"
WHERE "t-1"."expr-1" < 4
GROUP BY "g"."number"

>>> select(s.group for s in Student if max(s.gpa) < 4)

SELECT "s"."group"
FROM "Student" "s"
GROUP BY "s"."group"
HAVING MAX("s"."gpa") < 4

>>> select((s.group, avg(s.gpa)) for s in Student).order_by(lambda: avg(s.gpa))

SELECT "s"."group", AVG("s"."gpa")
FROM "Student" "s"
GROUP BY "s"."group"
ORDER BY AVG("s"."gpa")

>>> select((s.group, avg(s.gpa)) for s in Student).order_by(lambda: desc(avg(s.gpa)))

SELECT "s"."group", AVG("s"."gpa")
FROM "Student" "s"
GROUP BY "s"."group"
ORDER BY AVG("s"."gpa") DESC

>>> select((s.group, avg(s.gpa)) for s in Student).order_by(2)

SELECT "s"."group", AVG("s"."gpa")
FROM "Student" "s"
GROUP BY "s"."group"
ORDER BY 2

>>> select((s.group, avg(s.gpa)) for s in Student).order_by(-2)

SELECT "s"."group", AVG("s"."gpa")
FROM "Student" "s"
GROUP BY "s"."group"
ORDER BY 2 DESC

>>> select(sum(s.gpa) for s in Student)

SELECT coalesce(SUM("s"."gpa"), 0)
FROM "Student" "s"

>>> select(s.gpa for s in Student).sum()

SELECT coalesce(SUM("s"."gpa"), 0)
FROM "Student" "s"


# Other tests

Schema:
pony.orm.examples.university1

>>> select(s for s in Student if s.gpa > 3)

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
WHERE "s"."gpa" > 3

Oracle:
SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."GPA" > 3

>>> select(s for s in Student if s.group.number == 1)

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
WHERE "s"."group" = 1

Oracle:
SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."GROUP" = 1

>>> select(c for c in Course if count(c.students) > 3)

SELECT "c"."name", "c"."semester"
FROM "Course" "c"
  LEFT JOIN "Course_Student" "t-1"
    ON "c"."name" = "t-1"."course_name" AND "c"."semester" = "t-1"."course_semester"
GROUP BY "c"."name", "c"."semester"
HAVING COUNT(DISTINCT "t-1"."student") > 3

Oracle:

SELECT "c"."NAME", "c"."SEMESTER"
FROM "COURSE" "c"
  LEFT JOIN "COURSE_STUDENT" "t-1"
    ON "c"."NAME" = "t-1"."COURSE_NAME" AND "c"."SEMESTER" = "t-1"."COURSE_SEMESTER"
GROUP BY "c"."NAME", "c"."SEMESTER"
HAVING COUNT(DISTINCT "t-1"."STUDENT") > 3

>>> select(s for s in Student if count(s.courses) > 3)

SELECT "s"."id"
FROM "Student" "s"
  LEFT JOIN "Course_Student" "t-1"
    ON "s"."id" = "t-1"."student"
GROUP BY "s"."id"
HAVING COUNT("t-1"."ROWID") > 3

Oracle:

SELECT "s"."ID"
FROM "STUDENT" "s"
  LEFT JOIN "COURSE_STUDENT" "t-1"
    ON "s"."ID" = "t-1"."STUDENT"
GROUP BY "s"."ID"
HAVING COUNT("t-1"."ROWID") > 3

>>> select(s for s in Student).for_update()[:3]

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
LIMIT 3

Oracle:

SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."ROWID" IN (
    SELECT * FROM (
        SELECT "s"."ROWID" AS "row-id"
        FROM "STUDENT" "s"
    ) WHERE ROWNUM <= 3
    )
FOR UPDATE

>>> select(s for s in Student).order_by(Student.name).for_update()[:3]

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
ORDER BY "s"."name"
LIMIT 3

Oracle:

SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."ROWID" IN (
    SELECT * FROM (
        SELECT "s"."ROWID" AS "row-id"
        FROM "STUDENT" "s"
        ORDER BY "s"."NAME"
    ) WHERE ROWNUM <= 3
    )
ORDER BY "s"."NAME"
FOR UPDATE

>>> select(s for s in Student).order_by(Student.name).for_update()[3:6]

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
ORDER BY "s"."name"
LIMIT 3 OFFSET 3

Oracle:

SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."ROWID" IN (
    SELECT t."row-id" FROM (
        SELECT t.*, ROWNUM "row-num" FROM (
            SELECT "s"."ROWID" AS "row-id"
            FROM "STUDENT" "s"
            ORDER BY "s"."NAME"
        ) t WHERE ROWNUM <= 6
    ) t WHERE "row-num" > 3
    )
ORDER BY "s"."NAME"
FOR UPDATE

>>> select(s for s in Student).for_update()[3:6]

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
LIMIT 3 OFFSET 3

Oracle:

SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."ROWID" IN (
    SELECT t."row-id" FROM (
        SELECT t.*, ROWNUM "row-num" FROM (
            SELECT "s"."ROWID" AS "row-id"
            FROM "STUDENT" "s"
        ) t WHERE ROWNUM <= 6
    ) t WHERE "row-num" > 3
    )
FOR UPDATE

>>> select((g, count(s)) for g in Group for s in g.students)

SELECT "g"."number", COUNT(DISTINCT "s"."id")
FROM "Group" "g", "Student" "s"
WHERE "g"."number" = "s"."group"
GROUP BY "g"."number"

Oracle:

SELECT "g"."NUMBER", COUNT(DISTINCT "s"."ID")
FROM "GROUP" "g", "STUDENT" "s"
WHERE "g"."NUMBER" = "s"."GROUP"
GROUP BY "g"."NUMBER"

PostgreSQL:

SELECT "g"."number", COUNT(DISTINCT "s"."id")
FROM "group" "g", "student" "s"
WHERE "g"."number" = "s"."group"
GROUP BY "g"."number"

>>> select((s, count(c)) for s in Student for c in s.courses)

SELECT DISTINCT "s"."id", COUNT(DISTINCT "c"."ROWID")
FROM "Student" "s", "Course_Student" "t-1", "Course" "c"
WHERE "s"."id" = "t-1"."student"
  AND "t-1"."course_name" = "c"."name"
  AND "t-1"."course_semester" = "c"."semester"
GROUP BY "s"."id"

Oracle:

SELECT DISTINCT "s"."ID", COUNT(DISTINCT "c"."ROWID")
FROM "STUDENT" "s", "COURSE_STUDENT" "t-1", "COURSE" "c"
WHERE "s"."ID" = "t-1"."STUDENT"
  AND "t-1"."COURSE_NAME" = "c"."NAME"
  AND "t-1"."COURSE_SEMESTER" = "c"."SEMESTER"
GROUP BY "s"."ID"

PostgreSQL:

SELECT DISTINCT "s"."id", COUNT(DISTINCT case when ("t-1"."course_name", "t-1"."course_semester") IS NULL then null else ("t-1"."course_name", "t-1"."course_semester") end)
FROM "student" "s", "course_student" "t-1"
WHERE "s"."id" = "t-1"."student"
GROUP BY "s"."id"

>>> x = '123'
>>> select(s for s in Student if s.tel == x)[:]

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
WHERE "s"."tel" = ?

Oracle:

SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."TEL" = :p1

>>> x = ''
>>> select(s for s in Student if s.tel == x)[:]

Oracle:

SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."TEL" IS NULL

>>> x = ''
>>> select(s for s in Student).filter(lambda s: s.tel == x)[:]

Oracle:

SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE "s"."TEL" IS NULL

>>> select(s.name for s in Student if s.name in (s.name for s in Student if count() > 1))[:]

SELECT DISTINCT "s"."name"
FROM "Student" "s"
WHERE "s"."name" IN (
    SELECT "s-2"."name"
    FROM "Student" "s-2"
    GROUP BY "s-2"."name"
    HAVING COUNT(*) > 1
    )

>>> empty_list = []
>>> select(s.name for s in Student if s.id in empty_list)

SELECT DISTINCT "s"."name"
FROM "Student" "s"
WHERE 0 = 1

>>> empty_list = []
>>> select(s.name for s in Student if s.id not in empty_list)

SELECT DISTINCT "s"."name"
FROM "Student" "s"
WHERE 1 = 1

>>> select(s.name for s in Student)[:]

SELECT DISTINCT "s"."name"
FROM "Student" "s"

>>> select(s.name for s in Student).without_distinct()[:]

SELECT "s"."name"
FROM "Student" "s"

>>> select(s.name for s in Student).without_distinct().distinct()[:]

SELECT DISTINCT "s"."name"
FROM "Student" "s"

>>> select(s.name for s in Student).without_distinct().distinct().without_distinct()[:]

SELECT "s"."name"
FROM "Student" "s"

>>> select(s.name for s in Student).first()

SELECT "s"."name"
FROM "Student" "s"
ORDER BY 1
LIMIT 1

>>> select(s.name for s in Student).without_distinct().first()

SELECT "s"."name"
FROM "Student" "s"
ORDER BY 1
LIMIT 1

>>> select(s.name for s in Student)[4:5]

SELECT DISTINCT "s"."name"
FROM "Student" "s"
LIMIT 1 OFFSET 4

>>> select(s for s in Student if (s.group, s.gpa) in select((s2.group, max(s2.gpa)) for s2 in Student))

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
WHERE EXISTS (
    SELECT 1
    FROM "Student" "s2"
    GROUP BY "s2"."group"
    HAVING "s"."group" = "s2"."group"
      AND "s"."gpa" = MAX("s2"."gpa")
    )

PostgreSQL:

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "student" "s"
WHERE ("s"."group", "s"."gpa") IN (
    SELECT "s2"."group", MAX("s2"."gpa")
    FROM "student" "s2"
    GROUP BY "s2"."group"
    )

>>> select(s for s in Student if (s.group, s.gpa) not in select((s2.group, max(s2.gpa)) for s2 in Student))

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
WHERE NOT EXISTS (
    SELECT 1
    FROM "Student" "s2"
    GROUP BY "s2"."group"
    HAVING "s"."group" = "s2"."group"
      AND "s"."gpa" = MAX("s2"."gpa")
    )

PostgreSQL:

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "student" "s"
WHERE ("s"."group", "s"."gpa") NOT IN (
    SELECT "s2"."group", MAX("s2"."gpa")
    FROM "student" "s2"
    GROUP BY "s2"."group"
    HAVING MAX("s2"."gpa") IS NOT NULL
    )

# Complex aggregations:

Schema:
pony.orm.examples.university1

>>> count(g for g in Group if count(g.students) > 0 and g.number > 101)

SELECT COUNT(*)
FROM (
    SELECT "g"."number"
        FROM "Group" "g"
      LEFT JOIN "Student" "student"
        ON "g"."number" = "student"."group"
    WHERE "g"."number" > 101
    GROUP BY "g"."number"
    HAVING COUNT(DISTINCT "student"."id") > 0
    ) "t"

>>> count(g for g in Group if count(s for s in g.students) > 0 and g.number > 101)

SELECT COUNT(*)
FROM "Group" "g"
WHERE (
    SELECT COUNT(DISTINCT "s"."id")
    FROM "Student" "s"
    WHERE "g"."number" = "s"."group"
    ) > 0
  AND "g"."number" > 101

>>> sum(s.gpa for s in Student if count(s.courses) > 3 and s.gpa > 3.5)

SELECT coalesce(SUM("s"."gpa"), 0)
FROM (
    SELECT "s"."gpa"
        FROM "Student" "s"
      LEFT JOIN "Course_Student" "t-1"
        ON "s"."id" = "t-1"."student"
    WHERE "s"."gpa" > 3.5
    GROUP BY "s"."gpa"
    HAVING COUNT("t-1"."ROWID") > 3
    ) "s"

>>> sum(s.dob.year for s in Student if count(s.courses) > 3 and s.gpa > 3.5)

SELECT coalesce(SUM("t"."expr"), 0)
FROM (
    SELECT cast(substr("s"."dob", 1, 4) as integer) AS "expr"
        FROM "Student" "s"
      LEFT JOIN "Course_Student" "t-1"
        ON "s"."id" = "t-1"."student"
    WHERE "s"."gpa" > 3.5
    GROUP BY cast(substr("s"."dob", 1, 4) as integer)
    HAVING COUNT("t-1"."ROWID") > 3
    ) "t"

# Bulk delete:

>>> select(s for s in Student if s.gpa > 3).delete(bulk=True)

DELETE FROM "Student"
WHERE "gpa" > 3

>>> select(s for s in Student if s.group.dept.number == 1).delete(bulk=True)

DELETE FROM "Student"
WHERE "id" IN (
    SELECT "s"."id"
    FROM "Student" "s", "Group" "group"
    WHERE "group"."dept" = 1
      AND "s"."group" = "group"."number"
    )

MySQL:

DELETE s FROM `student` `s`
  INNER JOIN `group` `group`
    ON `s`.`group` = `group`.`number`
WHERE `group`.`dept` = 1

PostgreSQL:

DELETE FROM "student"
WHERE "id" IN (
    SELECT "s"."id"
    FROM "student" "s", "group" "group"
    WHERE "group"."dept" = 1
      AND "s"."group" = "group"."number"
    )

Oracle:

DELETE FROM "STUDENT"
WHERE "ID" IN (
    SELECT "s"."ID"
    FROM "STUDENT" "s", "GROUP" "group"
    WHERE "group"."DEPT" = 1
      AND "s"."GROUP" = "group"."NUMBER"
    )

>>> select(c for c in Course if c.dept.name.startswith('D')).delete(bulk=True)

DELETE FROM "Course"
WHERE "ROWID" IN (
    SELECT "c"."ROWID"
    FROM "Course" "c", "Department" "department"
    WHERE "department"."name" LIKE 'D%'
      AND "c"."dept" = "department"."number"
    )

MySQL:

DELETE c FROM `course` `c`
  INNER JOIN `department` `department`
    ON `c`.`dept` = `department`.`number`
WHERE `department`.`name` LIKE 'D%%'

PostgreSQL:

DELETE FROM "course"
WHERE ("name", "semester") IN (
    SELECT "c"."name", "c"."semester"
    FROM "course" "c", "department" "department"
    WHERE "department"."name" LIKE 'D%%'
      AND "c"."dept" = "department"."number"
    )

Oracle:

DELETE FROM "COURSE"
WHERE "ROWID" IN (
    SELECT "c"."ROWID"
    FROM "COURSE" "c", "DEPARTMENT" "department"
    WHERE "department"."NAME" LIKE 'D%'
      AND "c"."DEPT" = "department"."NUMBER"
    )

>>> select(s for s in Student if s.gpa > 3 and s not in (s2 for s2 in Student if s2.group.dept.name.startswith('A'))).delete(bulk=True)

DELETE FROM "Student"
WHERE "gpa" > 3
  AND "id" NOT IN (
    SELECT "s2"."id"
    FROM "Student" "s2", "Group" "group", "Department" "department"
    WHERE "department"."name" LIKE 'A%'
      AND "s2"."group" = "group"."number"
      AND "group"."dept" = "department"."number"
    )

# MySQL does not support such queries

PostgreSQL:

DELETE FROM "student"
WHERE "gpa" > 3
  AND "id" NOT IN (
    SELECT "s2"."id"
    FROM "student" "s2", "group" "group", "department" "department"
    WHERE "department"."name" LIKE 'A%%'
      AND "s2"."group" = "group"."number"
      AND "group"."dept" = "department"."number"
    )

Oracle:

DELETE FROM "STUDENT"
WHERE "GPA" > 3
  AND "ID" NOT IN (
    SELECT "s2"."ID"
    FROM "STUDENT" "s2", "GROUP" "group", "DEPARTMENT" "department"
    WHERE "department"."NAME" LIKE 'A%'
      AND "s2"."GROUP" = "group"."NUMBER"
      AND "group"."DEPT" = "department"."NUMBER"
    )

>>> select(s for s in Student if exists(s2 for s2 in Student if s.gpa > s2.gpa)).delete(bulk=True)

DELETE FROM "Student"
WHERE "id" IN (
    SELECT "s"."id"
    FROM "Student" "s"
    WHERE EXISTS (
        SELECT 1
        FROM "Student" "s2"
        WHERE "s"."gpa" > "s2"."gpa"
        )
    )

PostgreSQL:

DELETE FROM "student"
WHERE "id" IN (
    SELECT "s"."id"
    FROM "student" "s"
    WHERE EXISTS (
        SELECT 1
        FROM "student" "s2"
        WHERE "s"."gpa" > "s2"."gpa"
        )
    )

Oracle:

DELETE FROM "STUDENT"
WHERE "ID" IN (
    SELECT "s"."ID"
    FROM "STUDENT" "s"
    WHERE EXISTS (
        SELECT 1
        FROM "STUDENT" "s2"
        WHERE "s"."GPA" > "s2"."GPA"
        )
    )

# Test UPPER/LOWER functions:

>>> select(s.name.upper() for s in Student)

SELECT DISTINCT py_upper("s"."name")
FROM "Student" "s"

PostgreSQL:

SELECT DISTINCT upper("s"."name")
FROM "student" "s"

# Test modulo division operator

>>> select(s for s in Student if s.id % 2 == 0)

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
WHERE ("s"."id" % 2) = 0

PostgreSQL:

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "student" "s"
WHERE ("s"."id" %% 2) = 0

MySQL:

SELECT `s`.`id`, `s`.`name`, `s`.`dob`, `s`.`tel`, `s`.`gpa`, `s`.`group`
FROM `student` `s`
WHERE (`s`.`id` %% 2) = 0

Oracle:

SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
FROM "STUDENT" "s"
WHERE MOD("s"."ID", 2) = 0

# Test group_concat:

>>> select((g, group_concat(s.name, '+')) for g in Group for s in g.students)

SELECT "g"."number", GROUP_CONCAT("s"."name", '+')
FROM "Group" "g", "Student" "s"
WHERE "g"."number" = "s"."group"
GROUP BY "g"."number"

PostgreSQL:

SELECT "g"."number", string_agg("s"."name"::text, '+')
FROM "group" "g", "student" "s"
WHERE "g"."number" = "s"."group"
GROUP BY "g"."number"

MySQL:

SELECT `g`.`number`, GROUP_CONCAT(`s`.`name`, '+')
FROM `group` `g`, `student` `s`
WHERE `g`.`number` = `s`.`group`
GROUP BY `g`.`number`

Oracle:

SELECT "g"."NUMBER", LISTAGG("s"."NAME", '+') WITHIN GROUP(ORDER BY 1)
FROM "GROUP" "g", "STUDENT" "s"
WHERE "g"."NUMBER" = "s"."GROUP"
GROUP BY "g"."NUMBER"

# Test offset without limit

>>> select(s for s in Student)[3:]

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "Student" "s"
LIMIT -1 OFFSET 3

PostgreSQL:

SELECT "s"."id", "s"."name", "s"."dob", "s"."tel", "s"."gpa", "s"."group"
FROM "student" "s"
LIMIT null OFFSET 3

MySQL:

SELECT `s`.`id`, `s`.`name`, `s`.`dob`, `s`.`tel`, `s`.`gpa`, `s`.`group`
FROM `student` `s`
LIMIT 18446744073709551615 OFFSET 3

Oracle:

SELECT t.* FROM (
    SELECT t.*, ROWNUM "row-num" FROM (
        SELECT "s"."ID", "s"."NAME", "s"."DOB", "s"."TEL", "s"."GPA", "s"."GROUP"
        FROM "STUDENT" "s"
    ) t 
) t WHERE "row-num" > 3

