MetaCodeContext#

class swordfish._connection.MetaCodeContext(impl)#

Used for generating meta code.

示例

>>> with sf.meta_code() as m:
...     code = m.var("a")
>>> code
MetaCode(< a >)
参数:

impl (MetaCodeContextImpl)

var(name)#

Generates meta code representing a variable by its name.

参数:

name (str) -- The name of the variable.

返回:

The generated meta code.

返回类型:

MetaCode

示例

>>> with sf.meta_code() as m:
...     code = m.var("a")
>>> code
MetaCode(< a >)
const(obj)#

Generates meta code representing a Constant.

参数:

obj (Constant) -- The constant object.

返回:

The generated meta code.

返回类型:

MetaCode

示例

>>> with sf.meta_code():
...     code = x.const(2)
>>> code
MetaCode(< 2 >)
col(name, *, qualifier=None)#

Generates meta code for a column.

参数:

  • name (str) -- The name of the column.

  • qualifier (str, optional) -- The qualifier for the column. Defaults to None.

返回:

The generated meta code.

返回类型:

MetaCode

示例

>>> with sf.meta_code():
...     code = x.col("id", qualifier="t")
>>> code
MetaCode(< t.id >)
col_alias(obj, name)#

Generates meta code for assigning an alias to a column or aliases to columns.

参数:

  • obj (MetaCode) -- The original meta code for the column.

  • name (Union[str, List[str]]) -- The alias name(s).

返回:

The meta code with the column alias applied.

返回类型:

MetaCode

示例

>>> with sf.meta_code():
...     code = x.col_alias(x.col("id"), "col1")
>>> code
MetaCode(< id as col1 >)
parse(expression)#

Parses a string expression into corresponding meta code.

参数:

expression (str) -- The expression to parse into meta code.

返回:

The parsed meta code corresponding to the expression.

返回类型:

MetaCode

示例

>>> with sf.meta_code():
...     code = x.parse("a == 5")
>>> code
MetaCode(< a == 5 >)
call(func, *args)#
返回类型:

MetaCode

make_table_joiner(func, *args)#
返回类型:

MetaCode

property case_#