sea-query 0.26.2

🌊 A dynamic query builder for MySQL, Postgres and SQLite
Documentation
use super::*;
use crate::extension::postgres::*;

impl QueryBuilder for PostgresQueryBuilder {
    fn placeholder(&self) -> (&str, bool) {
        ("$", true)
    }

    fn if_null_function(&self) -> &str {
        "COALESCE"
    }

    fn write_string_quoted(&self, string: &str, buffer: &mut String) {
        let escaped = self.escape_string(string);
        let string = if escaped.find('\\').is_some() {
            "E'".to_owned() + &escaped + "'"
        } else {
            "'".to_owned() + &escaped + "'"
        };
        write!(buffer, "{}", string).unwrap()
    }

    fn prepare_bin_oper(
        &self,
        bin_oper: &BinOper,
        sql: &mut SqlWriter,
        collector: &mut dyn FnMut(Value),
    ) {
        match bin_oper {
            BinOper::Matches => write!(sql, "@@").unwrap(),
            BinOper::Contains => write!(sql, "@>").unwrap(),
            BinOper::Contained => write!(sql, "<@").unwrap(),
            BinOper::Concatenate => write!(sql, "||").unwrap(),
            _ => self.prepare_bin_oper_common(bin_oper, sql, collector),
        }
    }

    fn prepare_function(
        &self,
        function: &Function,
        sql: &mut SqlWriter,
        collector: &mut dyn FnMut(Value),
    ) {
        match function {
            Function::PgFunction(function) => write!(
                sql,
                "{}",
                match function {
                    PgFunction::ToTsquery => "TO_TSQUERY",
                    PgFunction::ToTsvector => "TO_TSVECTOR",
                    PgFunction::PhrasetoTsquery => "PHRASETO_TSQUERY",
                    PgFunction::PlaintoTsquery => "PLAINTO_TSQUERY",
                    PgFunction::WebsearchToTsquery => "WEBSEARCH_TO_TSQUERY",
                    PgFunction::TsRank => "TS_RANK",
                    PgFunction::TsRankCd => "TS_RANK_CD",
                    #[cfg(feature = "postgres-array")]
                    PgFunction::Any => "ANY",
                    #[cfg(feature = "postgres-array")]
                    PgFunction::Some => "SOME",
                    #[cfg(feature = "postgres-array")]
                    PgFunction::All => "ALL",
                }
            )
            .unwrap(),
            _ => self.prepare_function_common(function, sql, collector),
        }
    }

    fn prepare_simple_expr(
        &self,
        simple_expr: &SimpleExpr,
        sql: &mut SqlWriter,
        collector: &mut dyn FnMut(Value),
    ) {
        match simple_expr {
            SimpleExpr::AsEnum(type_name, expr) => {
                let simple_expr = expr.clone().cast_as(SeaRc::clone(type_name));
                self.prepare_simple_expr_common(&simple_expr, sql, collector);
            }
            _ => QueryBuilder::prepare_simple_expr_common(self, simple_expr, sql, collector),
        }
    }

    fn prepare_order_expr(
        &self,
        order_expr: &OrderExpr,
        sql: &mut SqlWriter,
        collector: &mut dyn FnMut(Value),
    ) {
        if !matches!(order_expr.order, Order::Field(_)) {
            self.prepare_simple_expr(&order_expr.expr, sql, collector);
        }
        write!(sql, " ").unwrap();
        self.prepare_order(order_expr, sql, collector);
        match order_expr.nulls {
            None => (),
            Some(NullOrdering::Last) => write!(sql, " NULLS LAST").unwrap(),
            Some(NullOrdering::First) => write!(sql, " NULLS FIRST").unwrap(),
        }
    }

    fn prepare_query_statement(
        &self,
        query: &SubQueryStatement,
        sql: &mut SqlWriter,
        collector: &mut dyn FnMut(Value),
    ) {
        query.prepare_statement(self, sql, collector);
    }

    fn prepare_select_distinct(
        &self,
        select_distinct: &SelectDistinct,
        sql: &mut SqlWriter,
        _collector: &mut dyn FnMut(Value),
    ) {
        match select_distinct {
            SelectDistinct::All => write!(sql, "ALL").unwrap(),
            SelectDistinct::Distinct => write!(sql, "DISTINCT").unwrap(),
            SelectDistinct::DistinctOn(cols) => {
                write!(sql, "DISTINCT ON (").unwrap();
                cols.iter().fold(true, |first, c| {
                    if !first {
                        write!(sql, ", ").unwrap();
                    }
                    c.prepare(sql, self.quote());
                    false
                });
                write!(sql, ")").unwrap();
            }
            _ => {}
        };
    }
}