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Create SAM/BAM/CRAM Table

Source: R/duckhts.R
rduckhts_bam.Rd

Creates a DuckDB table from SAM, BAM, or CRAM files using the DuckHTS extension.

Usage

rduckhts_bam(
  con,
  table_name,
  path,
  region = NULL,
  index_path = NULL,
  reference = NULL,
  standard_tags = FALSE,
  auxiliary_tags = FALSE,
  sequence_encoding = NULL,
  quality_representation = NULL,
  cigar_representation = NULL,
  scan_mode = NULL,
  decompression_threads = 2,
  overwrite = FALSE
)

Arguments

con

A DuckDB connection with DuckHTS loaded

table_name

Name for the created table

path

Path to the SAM/BAM/CRAM file

region

Optional genomic region (e.g., "chr1:1000-2000")

index_path

Optional explicit path to index file (.bai/.csi/.crai)

reference

Optional reference file path for CRAM files

standard_tags

Logical. If TRUE, include typed standard SAMtags columns. Default FALSE.

auxiliary_tags

Logical. If TRUE, include AUXILIARY_TAGS map of non-standard tags. Default FALSE.

sequence_encoding

Character. Sequence encoding for the SEQ column: "string" (default) returns decoded bases as VARCHAR; "nt16" returns raw htslib nt16 4-bit codes as UTINYINT[].

quality_representation

Character. Quality representation for the QUAL column: "string" (default) returns canonical Phred+33 text; "phred" returns raw Phred values as UTINYINT[].

cigar_representation

Character. CIGAR representation for the CIGAR column: "string" (default) returns SAM text such as "36M"; "binary" returns packed BAM operations as UINTEGER[] where each element is (len << 4) | op.

scan_mode

Optional scan mode. Use "auto" (default extension behavior) or "sequential" to force full-file streaming instead of index-backed count/parallel scan paths. Sequential mode is incompatible with region.

decompression_threads

Integer. Number of htslib decompression worker threads per file handle. Default 2. Use 0 to disable worker threads.

overwrite

Logical. If TRUE, overwrites existing table

Value

Invisible TRUE on success

Examples

library(DBI)
library(duckdb)

con <- rduckhts_connect()
bam_path <- system.file("extdata", "range.bam", package = "Rduckhts")
rduckhts_bam(con, "reads", bam_path, overwrite = TRUE)
dbGetQuery(con, "SELECT COUNT(*) FROM reads WHERE FLAG & 4 = 0")
#>   count_star()
#> 1          112
dbDisconnect(con, shutdown = TRUE)