surrealdb/sql/statements/
show.rs

1use crate::ctx::Context;
2use crate::dbs::{Options, Transaction};
3use crate::doc::CursorDoc;
4use crate::err::Error;
5use crate::iam::{Action, ResourceKind};
6use crate::sql::{Base, Datetime, Table, Value};
7use derive::Store;
8use revision::revisioned;
9use serde::{Deserialize, Serialize};
10use std::fmt;
11
12#[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Serialize, Deserialize, Hash)]
13#[revisioned(revision = 1)]
14pub enum ShowSince {
15	Timestamp(Datetime),
16	Versionstamp(u64),
17}
18
19// ShowStatement is used to show changes in a table or database via
20// the SHOW CHANGES statement.
21#[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Serialize, Deserialize, Store, Hash)]
22#[revisioned(revision = 1)]
23pub struct ShowStatement {
24	pub table: Option<Table>,
25	pub since: ShowSince,
26	pub limit: Option<u32>,
27}
28
29impl ShowStatement {
30	/// Process this type returning a computed simple Value
31	pub(crate) async fn compute(
32		&self,
33		_ctx: &Context<'_>,
34		opt: &Options,
35		txn: &Transaction,
36		_doc: Option<&CursorDoc<'_>>,
37	) -> Result<Value, Error> {
38		// Selected DB?
39		opt.is_allowed(Action::View, ResourceKind::Table, &Base::Db)?;
40		// Clone transaction
41		let txn = txn.clone();
42		// Claim transaction
43		let mut run = txn.lock().await;
44		// Process the show query
45		let tb = self.table.as_deref();
46		let r = crate::cf::read(
47			&mut run,
48			opt.ns(),
49			opt.db(),
50			tb.map(|x| x.as_str()),
51			self.since.clone(),
52			self.limit,
53		)
54		.await?;
55		// Return the changes
56		let mut a = Vec::<Value>::new();
57		for r in r.iter() {
58			let v: Value = r.clone().into_value();
59			a.push(v);
60		}
61		let v: Value = Value::Array(crate::sql::array::Array(a));
62		Ok(v)
63	}
64}
65
66impl fmt::Display for ShowStatement {
67	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
68		write!(f, "SHOW CHANGES FOR")?;
69		match self.table {
70			Some(ref v) => write!(f, " TABLE {}", v)?,
71			None => write!(f, " DATABASE")?,
72		}
73		match self.since {
74			ShowSince::Timestamp(ref v) => write!(f, " SINCE {}", v)?,
75			ShowSince::Versionstamp(ref v) => write!(f, " SINCE {}", v)?,
76		}
77		if let Some(ref v) = self.limit {
78			write!(f, " LIMIT {}", v)?
79		}
80		Ok(())
81	}
82}
surrealdb/sql/statements/show.rs

surrealdb/sql/statements/
show.rs
