Kristaps Fabians Geikins
46 lines
1.0 KiB
TypeScript
46 lines
1.0 KiB
TypeScript
/* eslint-disable @typescript-eslint/no-explicit-any */
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/* eslint-disable @typescript-eslint/ban-types */
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import { Knex } from 'knex'
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export type BatchedSelectOptions = {
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/**
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* Maximum amount of items to pull in one batch
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* Defaults to: 100
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*/
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batchSize: number
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trx: Knex.Transaction
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}
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/**
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* Batches a SELECT query through the use of LIMIT/OFFSET
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*/
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export async function* executeBatchedSelect<
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TRecord extends {},
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TResult extends Array<any>
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>(
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selectQuery: Knex.QueryBuilder<TRecord, TResult>,
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options?: Partial<BatchedSelectOptions>
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): AsyncGenerator<TResult, void, unknown> {
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const { batchSize = 100, trx } = options || {}
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if (trx) selectQuery.transacting(trx)
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selectQuery.limit(batchSize)
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let hasMorePages = true
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let currentOffset = 0
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while (hasMorePages) {
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const q = selectQuery.clone().offset(currentOffset)
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const results = (await q) as TResult
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if (!results.length) {
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hasMorePages = false
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break
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} else {
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currentOffset += results.length
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}
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yield results
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}
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}
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