61 lines
2.1 KiB
Python
61 lines
2.1 KiB
Python
from __future__ import annotations
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from sqlglot import exp, generator, parser, tokens, transforms
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from sqlglot.dialects.dialect import Dialect, rename_func, strposition_sql as _strposition_sql
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from sqlglot.helper import seq_get
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class Tableau(Dialect):
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LOG_BASE_FIRST = False
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class Tokenizer(tokens.Tokenizer):
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IDENTIFIERS = [("[", "]")]
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QUOTES = ["'", '"']
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class Generator(generator.Generator):
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JOIN_HINTS = False
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TABLE_HINTS = False
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QUERY_HINTS = False
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TRANSFORMS = {
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**generator.Generator.TRANSFORMS,
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exp.Coalesce: rename_func("IFNULL"),
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exp.Select: transforms.preprocess([transforms.eliminate_distinct_on]),
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}
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PROPERTIES_LOCATION = {
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**generator.Generator.PROPERTIES_LOCATION,
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exp.VolatileProperty: exp.Properties.Location.UNSUPPORTED,
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}
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def if_sql(self, expression: exp.If) -> str:
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this = self.sql(expression, "this")
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true = self.sql(expression, "true")
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false = self.sql(expression, "false")
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return f"IF {this} THEN {true} ELSE {false} END"
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def count_sql(self, expression: exp.Count) -> str:
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this = expression.this
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if isinstance(this, exp.Distinct):
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return self.func("COUNTD", *this.expressions)
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return self.func("COUNT", this)
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def strposition_sql(self, expression: exp.StrPosition) -> str:
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has_occurrence = "occurrence" in expression.args
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return _strposition_sql(
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self,
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expression,
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func_name="FINDNTH" if has_occurrence else "FIND",
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supports_occurrence=has_occurrence,
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)
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class Parser(parser.Parser):
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FUNCTIONS = {
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**parser.Parser.FUNCTIONS,
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"COUNTD": lambda args: exp.Count(this=exp.Distinct(expressions=args)),
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"FIND": exp.StrPosition.from_arg_list,
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"FINDNTH": lambda args: exp.StrPosition(
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this=seq_get(args, 0), substr=seq_get(args, 1), occurrence=seq_get(args, 2)
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),
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}
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NO_PAREN_IF_COMMANDS = False
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