1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
|
from __future__ import annotations
import typing as t
from sqlglot import exp, generator, parser, tokens, transforms
from sqlglot.dialects.dialect import (
Dialect,
NormalizationStrategy,
any_value_to_max_sql,
arrow_json_extract_scalar_sql,
arrow_json_extract_sql,
concat_to_dpipe_sql,
count_if_to_sum,
no_ilike_sql,
no_pivot_sql,
no_tablesample_sql,
no_trycast_sql,
rename_func,
)
from sqlglot.tokens import TokenType
def _date_add_sql(self: SQLite.Generator, expression: exp.DateAdd) -> str:
modifier = expression.expression
modifier = modifier.name if modifier.is_string else self.sql(modifier)
unit = expression.args.get("unit")
modifier = f"'{modifier} {unit.name}'" if unit else f"'{modifier}'"
return self.func("DATE", expression.this, modifier)
def _transform_create(expression: exp.Expression) -> exp.Expression:
"""Move primary key to a column and enforce auto_increment on primary keys."""
schema = expression.this
if isinstance(expression, exp.Create) and isinstance(schema, exp.Schema):
defs = {}
primary_key = None
for e in schema.expressions:
if isinstance(e, exp.ColumnDef):
defs[e.name] = e
elif isinstance(e, exp.PrimaryKey):
primary_key = e
if primary_key and len(primary_key.expressions) == 1:
column = defs[primary_key.expressions[0].name]
column.append(
"constraints", exp.ColumnConstraint(kind=exp.PrimaryKeyColumnConstraint())
)
schema.expressions.remove(primary_key)
else:
for column in defs.values():
auto_increment = None
for constraint in column.constraints:
if isinstance(constraint.kind, exp.PrimaryKeyColumnConstraint):
break
if isinstance(constraint.kind, exp.AutoIncrementColumnConstraint):
auto_increment = constraint
if auto_increment:
column.constraints.remove(auto_increment)
return expression
class SQLite(Dialect):
# https://sqlite.org/forum/forumpost/5e575586ac5c711b?raw
NORMALIZATION_STRATEGY = NormalizationStrategy.CASE_INSENSITIVE
SUPPORTS_SEMI_ANTI_JOIN = False
TYPED_DIVISION = True
SAFE_DIVISION = True
class Tokenizer(tokens.Tokenizer):
IDENTIFIERS = ['"', ("[", "]"), "`"]
HEX_STRINGS = [("x'", "'"), ("X'", "'"), ("0x", ""), ("0X", "")]
class Parser(parser.Parser):
FUNCTIONS = {
**parser.Parser.FUNCTIONS,
"EDITDIST3": exp.Levenshtein.from_arg_list,
}
class Generator(generator.Generator):
JOIN_HINTS = False
TABLE_HINTS = False
QUERY_HINTS = False
NVL2_SUPPORTED = False
TYPE_MAPPING = {
**generator.Generator.TYPE_MAPPING,
exp.DataType.Type.BOOLEAN: "INTEGER",
exp.DataType.Type.TINYINT: "INTEGER",
exp.DataType.Type.SMALLINT: "INTEGER",
exp.DataType.Type.INT: "INTEGER",
exp.DataType.Type.BIGINT: "INTEGER",
exp.DataType.Type.FLOAT: "REAL",
exp.DataType.Type.DOUBLE: "REAL",
exp.DataType.Type.DECIMAL: "REAL",
exp.DataType.Type.CHAR: "TEXT",
exp.DataType.Type.NCHAR: "TEXT",
exp.DataType.Type.VARCHAR: "TEXT",
exp.DataType.Type.NVARCHAR: "TEXT",
exp.DataType.Type.BINARY: "BLOB",
exp.DataType.Type.VARBINARY: "BLOB",
}
TOKEN_MAPPING = {
TokenType.AUTO_INCREMENT: "AUTOINCREMENT",
}
TRANSFORMS = {
**generator.Generator.TRANSFORMS,
exp.AnyValue: any_value_to_max_sql,
exp.Concat: concat_to_dpipe_sql,
exp.CountIf: count_if_to_sum,
exp.Create: transforms.preprocess([_transform_create]),
exp.CurrentDate: lambda *_: "CURRENT_DATE",
exp.CurrentTime: lambda *_: "CURRENT_TIME",
exp.CurrentTimestamp: lambda *_: "CURRENT_TIMESTAMP",
exp.DateAdd: _date_add_sql,
exp.DateStrToDate: lambda self, e: self.sql(e, "this"),
exp.ILike: no_ilike_sql,
exp.JSONExtract: arrow_json_extract_sql,
exp.JSONExtractScalar: arrow_json_extract_scalar_sql,
exp.JSONBExtract: arrow_json_extract_sql,
exp.JSONBExtractScalar: arrow_json_extract_scalar_sql,
exp.Levenshtein: rename_func("EDITDIST3"),
exp.LogicalOr: rename_func("MAX"),
exp.LogicalAnd: rename_func("MIN"),
exp.Pivot: no_pivot_sql,
exp.Rand: rename_func("RANDOM"),
exp.Select: transforms.preprocess(
[
transforms.eliminate_distinct_on,
transforms.eliminate_qualify,
transforms.eliminate_semi_and_anti_joins,
]
),
exp.TableSample: no_tablesample_sql,
exp.TimeStrToTime: lambda self, e: self.sql(e, "this"),
exp.TryCast: no_trycast_sql,
}
PROPERTIES_LOCATION = {
k: exp.Properties.Location.UNSUPPORTED
for k, v in generator.Generator.PROPERTIES_LOCATION.items()
}
LIMIT_FETCH = "LIMIT"
def cast_sql(self, expression: exp.Cast, safe_prefix: t.Optional[str] = None) -> str:
if expression.is_type("date"):
return self.func("DATE", expression.this)
return super().cast_sql(expression)
def datediff_sql(self, expression: exp.DateDiff) -> str:
unit = expression.args.get("unit")
unit = unit.name.upper() if unit else "DAY"
sql = f"(JULIANDAY({self.sql(expression, 'this')}) - JULIANDAY({self.sql(expression, 'expression')}))"
if unit == "MONTH":
sql = f"{sql} / 30.0"
elif unit == "YEAR":
sql = f"{sql} / 365.0"
elif unit == "HOUR":
sql = f"{sql} * 24.0"
elif unit == "MINUTE":
sql = f"{sql} * 1440.0"
elif unit == "SECOND":
sql = f"{sql} * 86400.0"
elif unit == "MILLISECOND":
sql = f"{sql} * 86400000.0"
elif unit == "MICROSECOND":
sql = f"{sql} * 86400000000.0"
elif unit == "NANOSECOND":
sql = f"{sql} * 8640000000000.0"
else:
self.unsupported("DATEDIFF unsupported for '{unit}'.")
return f"CAST({sql} AS INTEGER)"
# https://www.sqlite.org/lang_aggfunc.html#group_concat
def groupconcat_sql(self, expression: exp.GroupConcat) -> str:
this = expression.this
distinct = expression.find(exp.Distinct)
if distinct:
this = distinct.expressions[0]
distinct_sql = "DISTINCT "
else:
distinct_sql = ""
if isinstance(expression.this, exp.Order):
self.unsupported("SQLite GROUP_CONCAT doesn't support ORDER BY.")
if expression.this.this and not distinct:
this = expression.this.this
separator = expression.args.get("separator")
return f"GROUP_CONCAT({distinct_sql}{self.format_args(this, separator)})"
def least_sql(self, expression: exp.Least) -> str:
if len(expression.expressions) > 1:
return rename_func("MIN")(self, expression)
return self.sql(expression, "this")
def transaction_sql(self, expression: exp.Transaction) -> str:
this = expression.this
this = f" {this}" if this else ""
return f"BEGIN{this} TRANSACTION"
|
