Windshaft-cartodb/lib/cartodb/utils/query-utils.js

74 lines
2.4 KiB
JavaScript

function prepareQuery(sql) {
var affectedTableRegexCache = {
bbox: /!bbox!/g,
scale_denominator: /!scale_denominator!/g,
pixel_width: /!pixel_width!/g,
pixel_height: /!pixel_height!/g
};
return sql
.replace(affectedTableRegexCache.bbox, 'ST_MakeEnvelope(0,0,0,0)')
.replace(affectedTableRegexCache.scale_denominator, '0')
.replace(affectedTableRegexCache.pixel_width, '1')
.replace(affectedTableRegexCache.pixel_height, '1');
}
module.exports.extractTableNames = function extractTableNames(query) {
return [
'SELECT * FROM CDB_QueryTablesText($windshaft$',
prepareQuery(query),
'$windshaft$) as tablenames'
].join('');
};
function getQueryRowEstimation(query) {
return 'select CDB_EstimateRowCount($windshaft$' + query + '$windshaft$) as rows';
}
module.exports.getQueryRowCount = getQueryRowEstimation;
module.exports.getAggregationMetadata = ctx => `
WITH
rowEstimation AS (
${getQueryRowEstimation(ctx.query)}
),
geometryType AS (
SELECT ST_GeometryType(the_geom) as geom_type
FROM (${ctx.query}) AS __cdb_query WHERE the_geom IS NOT NULL LIMIT 1
)
SELECT
rows AS count,
geom_type AS type
FROM rowEstimation, geometryType;
`;
/** Cast the column to epoch */
module.exports.columnCastTpl = function columnCastTpl(ctx) {
return `date_part('epoch', ${ctx.column})`;
};
/** If the column type is float, ignore any non numeric result (infinity / NaN) */
module.exports.handleFloatColumn = function handleFloatColumn(ctx) {
return `${!ctx.isFloatColumn ? `${ctx.column}` :
`nullif(nullif(nullif(${ctx.column}, 'infinity'::float), '-infinity'::float), 'NaN'::float)`
}`;
};
/** Count NULL appearances */
module.exports.countNULLs= function countNULLs(ctx) {
return `sum(CASE WHEN (${ctx.column} IS NULL) THEN 1 ELSE 0 END)`;
};
/** Count only infinity (positive and negative) appearances */
module.exports.countInfinites = function countInfinites(ctx) {
return `${!ctx.isFloatColumn ? `0` :
`sum(CASE WHEN (${ctx.column} = 'infinity'::float OR ${ctx.column} = '-infinity'::float) THEN 1 ELSE 0 END)`
}`;
};
/** Count only NaNs appearances*/
module.exports.countNaNs = function countNaNs(ctx) {
return `${!ctx.isFloatColumn ? `0` :
`sum(CASE WHEN (${ctx.column} = 'NaN'::float) THEN 1 ELSE 0 END)`
}`;
};