signalk-parquet/dist/utils/buffer-sql-builder.js

Vessel data Parquet file archive with automated value and geospatial triggers. History API compliant with cloud backups and queries.

"use strict";
/**
 * SQL fragment builders for federating the SQLite buffer into DuckDB queries.
 *
 * Per-path table architecture: each SignalK path has its own table in buffer.db.
 * Scalar tables have a `value` column; object tables have flattened `value_*` columns.
 *
 * Buffer rows reach DuckDB via a staged TEMP table (see buffer-staging.ts) rather
 * than an ATTACH of the live buffer.db — callers stage first and pass the staged
 * table name in. The WHERE clauses here re-apply the staging filters harmlessly
 * and add the per-request value/filter conditions.
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.buildBufferScalarSubquery = buildBufferScalarSubquery;
exports.buildBufferObjectSubquery = buildBufferObjectSubquery;
const sql_escape_1 = require("./sql-escape");
const path_filters_1 = require("./path-filters");
/**
 * Build a buffer subquery for a scalar (numeric) path.
 *
 * Output columns: signalk_timestamp, value
 * Matches raw-tier parquet schema so it can be UNION ALL'd directly.
 *
 * When filters are provided, rows are restricted to matching column values.
 */
function buildBufferScalarSubquery(stagedTable, context, signalkPath, fromIso, toIso, filters) {
    const pathStr = String(signalkPath);
    // Root-level paths without dots are string properties (name, mmsi, uuid, etc.)
    const isStringPath = !pathStr.includes('.');
    const valueExpr = isStringPath ? 'value' : 'TRY_CAST(value AS DOUBLE)';
    return `(SELECT
    signalk_timestamp,
    ${valueExpr} AS value,
    NULL::VARCHAR AS value_json
  FROM ${stagedTable}
  WHERE context = '${(0, sql_escape_1.escapeSqlString)(String(context))}'
    AND signalk_timestamp >= '${(0, sql_escape_1.escapeSqlString)(fromIso)}'
    AND signalk_timestamp < '${(0, sql_escape_1.escapeSqlString)(toIso)}'
    AND exported = 0
    AND value IS NOT NULL${(0, path_filters_1.buildBufferFilterClause)(filters)})`;
}
/**
 * Build a buffer subquery for an object path (e.g. navigation.position).
 *
 * Per-path tables already have flattened value_* columns, so no json_extract needed.
 *
 * When filters are provided, rows are restricted to matching column values.
 */
function buildBufferObjectSubquery(stagedTable, context, fromIso, toIso, components, bufferTableColumns, filters) {
    const componentSelects = Array.from(components.entries())
        .map(([_name, comp]) => {
        // If we know the buffer table's columns, output NULL for missing ones
        if (bufferTableColumns && !bufferTableColumns.has(comp.columnName)) {
            return `NULL::DOUBLE AS ${comp.columnName}`;
        }
        // Columns are already flattened in per-path tables — just SELECT them directly
        if (comp.dataType === 'numeric') {
            return `TRY_CAST(${comp.columnName} AS DOUBLE) AS ${comp.columnName}`;
        }
        return `CAST(${comp.columnName} AS VARCHAR) AS ${comp.columnName}`;
    })
        .join(',\n    ');
    return `(SELECT
    signalk_timestamp,
    ${componentSelects}
  FROM ${stagedTable}
  WHERE context = '${(0, sql_escape_1.escapeSqlString)(String(context))}'
    AND signalk_timestamp >= '${(0, sql_escape_1.escapeSqlString)(fromIso)}'
    AND signalk_timestamp < '${(0, sql_escape_1.escapeSqlString)(toIso)}'
    AND exported = 0
    AND value_json IS NOT NULL${(0, path_filters_1.buildBufferFilterClause)(filters)})`;
}
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