sql

Composed()

class psycopg2.sql.Composed(seq)

print(
    sql.Composed([sql.SQL("insert into "), sql.Identifier("table")])
        .as_string(conn)
)
# insert into "table"

print(
    sql.Identifier('foo') + sql.Identifier('bar')  # a Composed
        .join(', ').as_string(conn)
)
# "foo", "bar"

Identifier()

class psycopg2.sql.Identifier(string)

t1 = sql.Identifier("foo")
t2 = sql.Identifier("ba'r")
t3 = sql.Identifier('ba"z')

print(sql.SQL(', ').join([t1, t2, t3]).as_string(conn))
# "foo", "ba'r", "ba""z"

print(
    sql.SQL("select {} from {}")
        .format(sql.Identifier("table", "field"), sql.Identifier("schema", "table"))
        .as_string(conn)
)
# select "table"."field" from "schema"."table"

Literal()

class psycopg2.sql.Literal(wrapped)

s1 = sql.Literal("foo")
s2 = sql.Literal("ba'r")
s3 = sql.Literal(42)
print(sql.SQL(', ').join([s1, s2, s3]).as_string(conn))
# 'foo', 'ba''r', 42

Placeholder()

class psycopg2.sql.Placeholder(name=None)

names = ['foo', 'bar', 'baz']

print(
    sql.SQL("insert into table ({}) values ({})")
    .format(
        sql.SQL(', ').join(map(sql.Identifier, names)),
        sql.SQL(', ').join(sql.Placeholder() * len(names)))
    .as_string()
)
# insert into table ("foo", "bar", "baz") values (%s, %s, %s)

print(
    sql.SQL("insert into table ({}) values ({})")
        .format(
            sql.SQL(', ').join(map(sql.Identifier, names)),
            sql.SQL(', ').join(map(sql.Placeholder, names)))
        .as_string()
)
# insert into table ("foo", "bar", "baz") values (%(foo)s, %(bar)s, %(baz)s)

SQL()

class psycopg2.sql.SQL(string)

query = sql.SQL("select {0} from {1}").format(
    sql.SQL(', ').join([sql.Identifier('foo'), sql.Identifier('bar')]),
    sql.Identifier('table'))
query.as_string(conn)
# select "foo", "bar" from "table"

string

format(*args, **kwargs)

print(
    sql.SQL("select * from {} where {} = %s")
        .format(sql.Identifier('people'), sql.Identifier('id'))
        .as_string(conn)
)
# select * from "people" where "id" = %s

print(
    sql.SQL("select * from {tbl} where {pkey} = %s")
        .format(tbl=sql.Identifier('people'), pkey=sql.Identifier('id'))
        .as_string(conn)
)
# select * from "people" where "id" = %s

join(seq)

prin(
    sql.SQL(', ')
        .join(sql.Identifier(n) for n in ['foo', 'bar', 'baz'])
        .as_string(conn)
)
# "foo", "bar", "baz"