Grammar: adds support for CREATE/ALTER/DROP DATABASE for Postgres dia…

…lect (#2081)

src/sqlfluff/dialects/dialect_postgres.py

@@ -1555,6 +1555,166 @@ class DropMaterializedViewStatementSegment(BaseSegment):
     )
 
 
+@postgres_dialect.segment(replace=True)
+class CreateDatabaseStatementSegment(BaseSegment):
+    """A `CREATE DATABASE` statement.
+
+    As specified in https://www.postgresql.org/docs/14/sql-createdatabase.html
+    """
+
+    type = "create_database_statement"
+
+    match_grammar = StartsWith(Sequence("CREATE", "DATABASE"))
+
+    parse_grammar = Sequence(
+        "CREATE",
+        "DATABASE",
+        Ref("DatabaseReferenceSegment"),
+        Ref.keyword("WITH", optional=True),
+        AnyNumberOf(
+            Sequence(
+                "OWNER",
+                Ref("EqualsSegment", optional=True),
+                Ref("ObjectReferenceSegment"),
+            ),
+            Sequence(
+                "TEMPLATE",
+                Ref("EqualsSegment", optional=True),
+                Ref("ObjectReferenceSegment"),
+            ),
+            Sequence(
+                "ENCODING",
+                Ref("EqualsSegment", optional=True),
+                OneOf(Ref("QuotedLiteralSegment"), "DEFAULT"),
+            ),
+            OneOf(
+                # LOCALE This is a shortcut for setting LC_COLLATE and LC_CTYPE at once.
+                # If you specify this, you cannot specify either of those parameters.
+                Sequence(
+                    "LOCALE",
+                    Ref("EqualsSegment", optional=True),
+                    Ref("QuotedLiteralSegment"),
+                ),
+                AnyNumberOf(
+                    Sequence(
+                        "LC_COLLATE",
+                        Ref("EqualsSegment", optional=True),
+                        Ref("QuotedLiteralSegment"),
+                    ),
+                    Sequence(
+                        "LC_CTYPE",
+                        Ref("EqualsSegment", optional=True),
+                        Ref("QuotedLiteralSegment"),
+                    ),
+                ),
+            ),
+            Sequence(
+                "TABLESPACE",
+                Ref("EqualsSegment", optional=True),
+                Ref("ParameterNameSegment"),
+            ),
+            Sequence(
+                "ALLOW_CONNECTIONS",
+                Ref("EqualsSegment", optional=True),
+                Ref("BooleanLiteralGrammar"),
+            ),
+            Sequence(
+                "CONNECTION",
+                "LIMIT",
+                Ref("EqualsSegment", optional=True),
+                Ref("NumericLiteralSegment"),
+            ),
+            Sequence(
+                "IS_TEMPLATE",
+                Ref("EqualsSegment", optional=True),
+                Ref("BooleanLiteralGrammar"),
+            ),
+        ),
+    )
+
+
+@postgres_dialect.segment()
+class AlterDatabaseStatementSegment(BaseSegment):
+    """A `ALTER DATABASE` statement.
+
+    As specified in https://www.postgresql.org/docs/14/sql-alterdatabase.html
+    """
+
+    type = "alter_database_statement"
+
+    match_grammar = StartsWith(Sequence("ALTER", "DATABASE"))
+
+    parse_grammar = Sequence(
+        "ALTER",
+        "DATABASE",
+        Ref("DatabaseReferenceSegment"),
+        OneOf(
+            Sequence(
+                Ref.keyword("WITH", optional=True),
+                AnyNumberOf(
+                    Sequence("ALLOW_CONNECTIONS", Ref("BooleanLiteralGrammar")),
+                    Sequence(
+                        "CONNECTION",
+                        "LIMIT",
+                        Ref("NumericLiteralSegment"),
+                    ),
+                    Sequence("IS_TEMPLATE", Ref("BooleanLiteralGrammar")),
+                    min_times=1,
+                ),
+            ),
+            Sequence("RENAME", "TO", Ref("DatabaseReferenceSegment")),
+            Sequence(
+                "OWNER",
+                "TO",
+                OneOf(
+                    Ref("ObjectReferenceSegment"),
+                    "CURRENT_ROLE",
+                    "CURRENT_USER",
+                    "SESSION_USER",
+                ),
+            ),
+            Sequence("SET", "TABLESPACE", Ref("ParameterNameSegment")),
+            Sequence(
+                "SET",
+                Ref("ParameterNameSegment"),
+                OneOf(
+                    Sequence(
+                        OneOf("TO", Ref("EqualsSegment")),
+                        OneOf("DEFAULT", Ref("LiteralGrammar")),
+                    ),
+                    Sequence("FROM", "CURRENT"),
+                ),
+            ),
+            Sequence("RESET", OneOf("ALL", Ref("ParameterNameSegment"))),
+            optional=True,
+        ),
+    )
+
+
+@postgres_dialect.segment()
+class DropDatabaseStatementSegment(BaseSegment):
+    """A `DROP DATABASE` statement.
+
+    As specified in https://www.postgresql.org/docs/14/sql-dropdatabase.html
+    """
+
+    type = "drop_database_statement"
+
+    match_grammar = StartsWith(Sequence("DROP", "DATABASE"))
+
+    parse_grammar = Sequence(
+        "DROP",
+        "DATABASE",
+        Sequence("IF", "EXISTS", optional=True),
+        Ref("DatabaseReferenceSegment"),
+        Sequence(
+            Ref.keyword("WITH", optional=True),
+            Bracketed("FORCE"),
+            optional=True,
+        ),
+    )
+
+
 @postgres_dialect.segment()
 class LikeOptionSegment(BaseSegment):
     """Like Option Segment.
@@ -2414,6 +2574,8 @@ class StatementSegment(BaseSegment):
             Ref("AlterMaterializedViewStatementSegment"),
             Ref("DropMaterializedViewStatementSegment"),
             Ref("RefreshMaterializedViewStatementSegment"),
+            Ref("AlterDatabaseStatementSegment"),
+            Ref("DropDatabaseStatementSegment"),
         ],
     )
 

src/sqlfluff/dialects/dialect_postgres_keywords.py

@@ -879,6 +879,7 @@ def get_keywords(keyword_list, keyword_type):
 ]
 
 postgres_nondocs_keywords = [
+    ("ALLOW_CONNECTIONS", "non-reserved"),
     ("BUFFERS", "non-reserved"),
     ("CONNECT", "reserved"),
     ("COSTS", "non-reserved"),
@@ -890,8 +891,12 @@ def get_keywords(keyword_list, keyword_type):
     ("FORMAT", "non-reserved"),
     ("HASH", "non-reserved"),
     ("IGNORE", "non-reserved"),
+    ("IS_TEMPLATE", "non-reserved"),
     ("JSON", "non-reserved"),
+    ("LC_COLLATE", "non-reserved"),
+    ("LC_CTYPE", "non-reserved"),
     ("LIST", "non-reserved"),
+    ("LOCALE", "non-reserved"),
     ("MAIN", "non-reserved"),
     ("MODULUS", "non-reserved"),
     ("PLAIN", "non-reserved"),

test/fixtures/dialects/postgres/postgres_alter_database.sql

@@ -0,0 +1,31 @@
+ALTER DATABASE db;
+ALTER DATABASE db ALLOW_CONNECTIONS true;
+ALTER DATABASE db WITH ALLOW_CONNECTIONS true;
+ALTER DATABASE db CONNECTION LIMIT 10;
+ALTER DATABASE db WITH CONNECTION LIMIT 10;
+ALTER DATABASE db IS_TEMPLATE true;
+ALTER DATABASE db WITH IS_TEMPLATE true;
+ALTER DATABASE db IS_TEMPLATE true ALLOW_CONNECTIONS true;
+ALTER DATABASE db WITH IS_TEMPLATE true ALLOW_CONNECTIONS true;
+ALTER DATABASE db CONNECTION LIMIT 10 IS_TEMPLATE true ALLOW_CONNECTIONS true;
+ALTER DATABASE db WITH CONNECTION LIMIT 10 IS_TEMPLATE true ALLOW_CONNECTIONS true;
+
+ALTER DATABASE db RENAME TO new_db;
+ALTER DATABASE db OWNER TO other_role;
+ALTER DATABASE db OWNER TO CURRENT_ROLE;
+ALTER DATABASE db OWNER TO CURRENT_USER;
+ALTER DATABASE db OWNER TO SESSION_USER;
+
+-- Issue:2017
+ALTER DATABASE postgres SET password_encryption TO 'scram-sha-256';
+ALTER DATABASE db SET TABLESPACE new_tablespace;
+ALTER DATABASE db SET parameter1 TO 1;
+ALTER DATABASE db SET parameter1 TO 'some_value';
+ALTER DATABASE db SET parameter1 TO DEFAULT;
+ALTER DATABASE db SET parameter1 = 1;
+ALTER DATABASE db SET parameter1 = 'some_value';
+ALTER DATABASE db SET parameter1 = DEFAULT;
+ALTER DATABASE db SET parameter1 FROM CURRENT;
+
+ALTER DATABASE db RESET parameter1;
+ALTER DATABASE db RESET ALL;