EVN Data Archive TAP serviceEVN TAPivo://jive.eu/tapJoint Institute for VLBI ERICMark Kettenishttp://evn-vo.jive.eu/favicon.png2020-12-15T16:41:59ZMark KettenisOude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlandskettenis@jive.eu+31 521 596524virtual-observatoriescatalogsThe EVN Data Archive's TAP end point. The Table Access
Protocol (TAP) lets you execute queries against our database tables,
inspect various metadata, and upload your own data. It is thus the
VO's premier way to access public data holdings.
Tables exposed through this endpoint include: main from the evn schema, obscore from the ivoa schema, main from the radio schema, columns, groups, key_columns, keys, schemas, tables from the tap_schema schema.https://evn-vo.jive.eu/__system__/tap/run/infohttp://evn-vo.jive.eu/tapObscore-1.1Obscore-1.1ADQL2.02.1The Astronomical Data Query Language is the standard IVOA dialect of SQL; it contains a very general SELECT statement as well as some extensions for spherical geometry and higher mathematics.returns the authority part of an ivoid (or, more generally a URI).
So, ivo://org.gavo.dc/foo/bar#baz becomes org.gavo.dc.
The behaviour for anything that's not a full URI is undefined.gavo_ipix returns the q3c ipix for a long/lat pair (it simply wraps
the 13c_ang2ipix function).
This is probably only relevant when you play tricks with indices or
PPMXL ids.gavo_match returns 1 if the POSIX regular expression pattern
matches anything in string, 0 otherwise.returns the intersection of two MOCs.returns the union of two MOCs.returns the spectral value expr converted to dest_unit.
expr has to be in either energy, wavelength, or frequency, and dest_unit
must be a VOUnit giving another spectral unit (e.g., MHz, keV, nm, or
Angstrom). This is intended to let users express spectral constraints
in their preferred unit independently of the choice of unit in the
database. Examples::
gavo_specconv(obscore.em_min, "keV") > 300
gavo_specconv(obscore.em_max, "MHz") > 30
gavo_specconv(spectral_start, "Angstrom") > 4000
There is a variant of gavo_specconv accepting expr's unit in a third
argument.returns expr assumed to be in expr_unit expressed in dest_unit.
This is a variant of the two-argument gavo_specconv for when
the unit of expr is not known to the ADQL translator, either because
it because it is a literal or because it does not look like
a spectral unit. Examples::
gavo_specconv(656, 'nm', 'J') BETWEEN spectral_start AND spectral_end
gavo_specconv(arccos(phi)*incidence, 'Hz', 'eV')
Clearly, overriding known units is likely to yield bad results;
the translator therefore warns if an existing unit is overridden
with a different unit.returns 1 if matchagainst is term or narrower in the IVOA vocabulary
vocname, 0 otherwise.
This is intended for semantic querying. For instance,
gavo_vocmatch('datalink/core', 'calibration', semantics) would be 1
if semantics is any of calibration, bias, dark, or flat.
For RDF-flavoured vocabularies (strict trees), term will expand to the
entire branch rooted in term. For SKOS-flavoured vocabularies (where
narrower is not transitive), only directly narrower terms will be included.
Both the term and the vocabulary name must be string literals (i.e.,
constants). matchagainst can be any string-valued expression.The function transforms ADQL geometries between various reference systems.
geo can be a POINT, a CIRCLE, or a POLYGON, and the function will return a
geometry of the same type. In the current implementation, from_sys and
to_sys must be literal strings (i.e., they cannot be computed through
expressions or be taken from database columns).
All transforms are just simple rotations, which is only a rough
approximation to the actual relationships between reference systems
(in particular between FK4 and ICRS-based ones). Note that, in particular,
the epoch is not changed (i.e., no proper motions are applied).
We currently support the following reference frames: ICRS, FK5 (which
is treated as ICRS), FK4 (for B1950. without epoch-dependent corrections),
GALACTIC. Reference frame names are case-sensitive.The function takes two strings; the first is a list of words not
containing the hash sign (#), concatenated by hash signs, the second is
a word not containing the hash sign. It returns 1 if, compared
case-insensitively, the second argument is in the list of words coded in
the first argument. The behaviour in case the the second
argument contains a hash sign is unspecified.gavo_hasword returns 1 if needle shows up in haystack, 0 otherwise. This
is for "google-like"-searches in text-like fields. In word, you can
actually employ a fairly complex query language; see
https://www.postgresql.org/docs/current/textsearch.html
for details.returns a POINT corresponding to the center of the healpix with
the given index at the given order.Returns the index of the (nest) healpix with order containing the
spherical point (ra, dec).
An alternative, 2-argument form
ivo_healpix_index(order INTEGER, p POINT) -> BIGINT
is also available.The aggregate function returns a histogram of val with nbins+2 elements.
Assuming 0-based arrays, result[0] contains the number of underflows (i.e.,
val<lower), result[nbins+1] the number of overflows. Elements 1..nbins
are the counts in nbins bins of width (upper-lower)/nbins. Clients
will have to convert back to physical units using some external
communication, there currently is no (meta-) data as lower and upper in
the TAP response.The function returns 1 if the interval iv contains val, 0 otherwise.
The lower limit is always included in iv, behaviour on the upper
limit is column-specific.The function returns 1 if the interval [l1...h1] overlaps with
the interval [l2...h2]. For the purposes of this function,
the case l1=h2 or l2=h1 is treated as overlap. The function
returns 0 for non-overlapping intervals.ivo_nocasematch returns 1 if pattern matches value, 0 otherwise.
pattern is defined as for the SQL LIKE operator, but the
match is performed case-insensitively. This function in effect
provides a surrogate for the ILIKE SQL operator that is missing from
ADQL.
On this site, this is actually implemented using python's and SQL's
LOWER, so for everything except ASCII, your mileage will vary.The function returns a random number drawn from a normal distribution
with mean mu and width sigma.
Implementation note: Right now, the Gaussian is approximated by
summing up and scaling ten calls to random. This, hence, is not
very precise or fast. It might work for some use cases, and we
will provide a better implementation if this proves inadequate.gavo_simbadpoint queries simbad for an identifier and returns the
corresponding point. Note that identifier can only be a literal,
i.e., as simple string rather than a column name. This is because
our database cannot query simbad, and we probably wouldn't want
to fire off millions of simbad queries anyway; use simbad's own
TAP service for this kind of application.An aggregate function returning all values of
expression within a GROUP contcatenated with delimiterThe function converts a postgres timestamp to julian date.
This is naive; no corrections for timezones, let alone time
scales or the like are done; you can thus not expect this to be
good to second-precision unless you are careful in the construction
of the timestamp.The function converts a postgres timestamp to modified julian date.
This is naive; no corrections for timezones, let alone time
scales or the like are done; you can thus not expect this to be
good to second-precision unless you are careful in the construction
of the timestamp.Written after a table reference, TABLESAMPLE(10) will make the database only use 10% of the rows; these are `somewhat random' in that the system will use random blocks. This should be good enough when just testing queries (and much better than using TOP n).A geometry function creating MOCs. It either takes a string argument with an ASCII MOC ('4/13 17-18 8/3002'), or an order and another geometry.This is the standard SQL COALESCE for providing defaults in case of NULL values.You can compute with vectors here. See https://wiki.ivoa.net/twiki/bin/view/IVOA/ADQLVectorMath for an overview of the functions and operators available.The SQL92 CASE expressiontext/tab-separated-valuestsvtext/plaintxttext/csvcsv_baretext/csv;header=presentcsvapplication/jsonjsonapplication/geo+jsongeojsonapplication/x-votable+xmlvotableapplication/x-votable+xml;serialization=BINARY2votable/b2votableb2application/x-votable+xml;serialization=TABLEDATAtext/xmlvotable/tdvotabletdapplication/x-votable+xml;serialization=TABLEDATA;version=1.1text/xmlvotabletd1.1application/x-votable+xml;version=1.1text/xmlvotable1.1application/x-votable+xml;serialization=TABLEDATA;version=1.2text/xmlvotabletd1.2application/x-votable+xml;serialization=TABLEDATA;version=1.5vodmlapplication/x-votable+xml;version=1.5vodmlbtext/htmlhtmlapplication/fitsfits1728003600200002000000020000000http://evn-vo.jive.eu/__system__/tap/run/availabilityhttp://evn-vo.jive.eu/__system__/tap/run/capabilitieshttp://evn-vo.jive.eu/__system__/tap/run/tableMetadataRadioevnEVN Data Archive The data archive of the European VLBI Network (EVN). This archive
contains Very Long Baseline Interferometry (VLBI) visibility data from
observations of the EVN, the most sensitive VLBI array in the world.
In addition, the archive makes available various correlator and
pipeline products that give an impression of the data quality. In some
cases, preliminary images of calibrators and target sources are also
available.evn.main Visibility data from the EVN Data Archive.19224accrefAccess key for the datameta.ref.urlAccess.ReferencecharindexednullableownerOwner of the datacharnullableembargoDate the data will become/became publicacharnullablemimeMIME type of the file servedmeta.code.mimeAccess.FormatcharnullableaccsizeSize of the data in bytesbyteVOX:Image_FileSizeAccess.Sizelongnullableaccess_urlThe URL at which to obtain the data set.meta.ref.urlobscore:access.referencecharnullables_regionRegion covered by the observation, as a polygonpos.outline;obs.fieldobscore:char.spatialaxis.coverage.support.areacharnullables_decDec of (center of) observation, ICRSdegpos.eq.decobscore:char.spatialaxis.coverage.location.coord.position2d.value2.c2doublenullableobs_publisher_didDataset identifier assigned by the publisher.meta.ref.ivoidobscore:curation.publisherdidcharnullableem_maxMaximal wavelength represented within the data setmem.wl;stat.maxobscore:char.spectralaxis.coverage.bounds.limits.hilimitdoublenullableem_minMinimal wavelength represented within the data setmem.wl;stat.minobscore:char.spectralaxis.coverage.bounds.limits.lolimitdoublenullableem_res_powerSpectral resolving power lambda/delta lamdaspect.resolutionobscore:char.spectralaxis.resolution.resolpower.refvaldoublenullableem_xelNumber of elements (typically pixels) along the spectral axis.meta.numberobscore:Char.SpectralAxis.numBinslongnullablet_exptimeTotal exposure timestime.duration;obs.exposureobscore:char.timeaxis.coverage.support.extentfloatnullables_fovApproximate spatial extent for the region covered by the observationdegphys.angSize;instr.fovobscore:char.spatialaxis.coverage.bounds.extent.diameterdoublenullableobs_idUnique identifier for an observationmeta.idobscore:DataID.observationIDcharnullablepol_xelNumber of elements (typically pixels) along the polarization axis.meta.numberobscore:Char.PolarizationAxis.numBinslongnullables_raRA of (center of) observation, ICRSdegpos.eq.raobscore:char.spatialaxis.coverage.location.coord.position2d.value2.c1doublenullableaccess_estsizeEstimated size of data productkbytephys.size;meta.fileobscore:access.sizelongnullables_resolutionBest spatial resolution within the data setarcsecpos.angResolutionobscore:Char.SpatialAxis.Resolution.refval.valuedoublenullabletarget_nameObject a targeted observation targetedmeta.id;srcobscore:Target.Namecharnullablet_maxUpper bound of times represented in the data setdtime.end;obs.exposureobscore:char.timeaxis.coverage.bounds.limits.stoptimedoublenullablet_minLower bound of times represented in the data setdtime.start;obs.exposureobscore:char.timeaxis.coverage.bounds.limits.starttimedoublenullablet_resolutionMinimal significant time interval along the time axisstime.resolutionobscore:char.timeaxis.resolution.refval.valuefloatnullablet_xelNumber of elements (typically pixels) along the time axis.meta.numberobscore:Char.TimeAxis.numBinslongnullable
ivoaDefinition and support code for the ObsCore data model and table.ivoa.obscoreEVN Data Archive Obscore TableThe IVOA-defined obscore table, containing generic metadata for
datasets within this datacenter.dataproduct_typeHigh level scientific classification of the data product, taken from an enumerationmeta.code.classobscore:obsdataset.dataproducttypecharnullabledataproduct_subtypeData product specific typemeta.code.classobscore:obsdataset.dataproductsubtypecharnullablecalib_levelAmount of data processing that has been applied to the datameta.code;obs.calibobscore:obsdataset.caliblevelshortobs_collectionName of a data collection (e.g., project name) this data belongs tometa.idobscore:dataid.collectioncharnullableobs_idUnique identifier for an observationmeta.idobscore:DataID.observationIDcharnullableobs_titleFree-from title of the data setmeta.title;obsobscore:dataid.titlecharnullableobs_publisher_didDataset identifier assigned by the publisher.meta.ref.ivoidobscore:curation.publisherdidcharindexednullableobs_creator_didDataset identifier assigned by the creator.meta.idobscore:dataid.creatordidcharnullableaccess_urlThe URL at which to obtain the data set.meta.ref.urlobscore:access.referencecharnullableaccess_formatMIME type of the resource at access_urlmeta.code.mimeobscore:access.formatcharnullableaccess_estsizeEstimated size of data productkbytephys.size;meta.fileobscore:access.sizelongnullabletarget_nameObject a targeted observation targetedmeta.id;srcobscore:Target.Namecharnullabletarget_classClass of the target object (star, QSO, ...)src.classobscore:target.classcharnullables_raRA of (center of) observation, ICRSdegpos.eq.raobscore:char.spatialaxis.coverage.location.coord.position2d.value2.c1doubleindexednullables_decDec of (center of) observation, ICRSdegpos.eq.decobscore:char.spatialaxis.coverage.location.coord.position2d.value2.c2doubleindexednullables_fovApproximate spatial extent for the region covered by the observationdegphys.angSize;instr.fovobscore:char.spatialaxis.coverage.bounds.extent.diameterdoublenullables_regionRegion covered by the observation, as a polygonpos.outline;obs.fieldobscore:char.spatialaxis.coverage.support.areacharnullables_resolutionBest spatial resolution within the data setarcsecpos.angResolutionobscore:Char.SpatialAxis.Resolution.refval.valuedoublenullablet_minLower bound of times represented in the data setdtime.start;obs.exposureobscore:char.timeaxis.coverage.bounds.limits.starttimedoublenullablet_maxUpper bound of times represented in the data setdtime.end;obs.exposureobscore:char.timeaxis.coverage.bounds.limits.stoptimedoublenullablet_exptimeTotal exposure timestime.duration;obs.exposureobscore:char.timeaxis.coverage.support.extentfloatnullablet_resolutionMinimal significant time interval along the time axisstime.resolutionobscore:char.timeaxis.resolution.refval.valuefloatnullableem_minMinimal wavelength represented within the data setmem.wl;stat.minobscore:char.spectralaxis.coverage.bounds.limits.lolimitdoublenullableem_maxMaximal wavelength represented within the data setmem.wl;stat.maxobscore:char.spectralaxis.coverage.bounds.limits.hilimitdoublenullableem_res_powerSpectral resolving power lambda/delta lamdaspect.resolutionobscore:char.spectralaxis.resolution.resolpower.refvaldoublenullableo_ucdUCD for the product's observablemeta.ucdobscore:char.observableaxis.ucdcharnullablepol_statesList of polarization states in the data setmeta.code;phys.polarizationobscore:Char.PolarizationAxis.stateListcharnullablefacility_nameName of the facility at which data was takenmeta.id;instr.telobscore:Provenance.ObsConfig.facility.namecharnullableinstrument_nameName of the instrument that produced the datameta.id;instrobscore:Provenance.ObsConfig.instrument.namecharnullables_xel1Number of elements (typically pixels) along the first spatial axis.meta.numberobscore:Char.SpatialAxis.numBins1longnullables_xel2Number of elements (typically pixels) along the second spatial axis.meta.numberobscore:Char.SpatialAxis.numBins2longnullablet_xelNumber of elements (typically pixels) along the time axis.meta.numberobscore:Char.TimeAxis.numBinslongnullableem_xelNumber of elements (typically pixels) along the spectral axis.meta.numberobscore:Char.SpectralAxis.numBinslongnullablepol_xelNumber of elements (typically pixels) along the polarization axis.meta.numberobscore:Char.PolarizationAxis.numBinslongnullables_pixel_scaleSampling period in world coordinate units along the spatial axisarcsecphys.angSize;instr.pixelobscore:Char.SpatialAxis.Sampling.RefVal.SamplingPerioddoublenullableem_ucdNature of the product's spectral axis (typically, em.freq, em.wl, or em.energy)meta.ucdobscore:Char.SpectralAxis.ucdcharnullablepreviewURL of a preview (low-resolution, quick-to-retrieve representation) of the data.meta.ref.url;meta.previewcharnullablesource_tableName of a TAP-queriable table this data originates from. This source table usually provides more information on the the data than what is given in obscore. See the TAP_SCHEMA of the originating TAP server for details.meta.id;meta.tablecharnullable
radioEVN Data Archive The data archive of the European VLBI Network (EVN). This archive
contains Very Long Baseline Interferometry (VLBI) visibility data from
observations of the EVN, the most sensitive VLBI array in the world.
In addition, the archive makes available various correlator and
pipeline products that give an impression of the data quality. In some
cases, preliminary images of calibrators and target sources are also
available.radio.main Visibility data from the EVN Data Archive.25302accrefAccess key for the datameta.ref.urlAccess.ReferencecharindexednullableownerOwner of the datacharnullableembargoDate the data will become/became publicacharnullablemimeMIME type of the file servedmeta.code.mimeAccess.FormatcharnullableaccsizeSize of the data in bytesbyteVOX:Image_FileSizeAccess.Sizelongnullableaccess_urlThe URL at which to obtain the data set.meta.ref.urlobscore:access.referencecharnullables_regionRegion covered by the observation, as a polygonpos.outline;obs.fieldobscore:char.spatialaxis.coverage.support.areacharnullables_decDec of (center of) observation, ICRSdegpos.eq.decobscore:char.spatialaxis.coverage.location.coord.position2d.value2.c2doublenullableobs_publisher_didDataset identifier assigned by the publisher.meta.ref.ivoidobscore:curation.publisherdidcharnullableem_maxMaximal wavelength represented within the data setmem.wl;stat.maxobscore:char.spectralaxis.coverage.bounds.limits.hilimitdoublenullableem_minMinimal wavelength represented within the data setmem.wl;stat.minobscore:char.spectralaxis.coverage.bounds.limits.lolimitdoublenullableem_res_powerSpectral resolving power lambda/delta lamdaspect.resolutionobscore:char.spectralaxis.resolution.resolpower.refvaldoublenullableem_xelNumber of elements (typically pixels) along the spectral axis.meta.numberobscore:Char.SpectralAxis.numBinslongnullablet_exptimeTotal exposure timestime.duration;obs.exposureobscore:char.timeaxis.coverage.support.extentfloatnullables_fovApproximate spatial extent for the region covered by the observationdegphys.angSize;instr.fovobscore:char.spatialaxis.coverage.bounds.extent.diameterdoublenullableobs_idUnique identifier for an observationmeta.idobscore:DataID.observationIDcharnullablepol_xelNumber of elements (typically pixels) along the polarization axis.meta.numberobscore:Char.PolarizationAxis.numBinslongnullables_raRA of (center of) observation, ICRSdegpos.eq.raobscore:char.spatialaxis.coverage.location.coord.position2d.value2.c1doublenullableaccess_estsizeEstimated size of data productkbytephys.size;meta.fileobscore:access.sizelongnullables_resolutionBest spatial resolution within the data setarcsecpos.angResolutionobscore:Char.SpatialAxis.Resolution.refval.valuedoublenullabletarget_nameObject a targeted observation targetedmeta.id;srcobscore:Target.Namecharnullablet_maxUpper bound of times represented in the data setdtime.end;obs.exposureobscore:char.timeaxis.coverage.bounds.limits.stoptimedoublenullablet_minLower bound of times represented in the data setdtime.start;obs.exposureobscore:char.timeaxis.coverage.bounds.limits.starttimedoublenullablet_resolutionMinimal significant time interval along the time axisstime.resolutionobscore:char.timeaxis.resolution.refval.valuefloatnullablet_xelNumber of elements (typically pixels) along the time axis.meta.numberobscore:Char.TimeAxis.numBinslongnullable
tap_schema EVN Data Archive's Table Access Protocol (TAP) service with
table metadata.tap_schema.schemasSchemas containing tables available for ADQL querying.schema_nameFully qualified schema namecharindexedprimarydescriptionBrief description of the schemaunicodeCharnullableutypeutype if schema corresponds to a data modelcharnullableschema_indexSuggested position this schema should take in a sorted list of schemas from this data center.intnullable
tap_schema.tablesTables available for ADQL querying.schema_nameFully qualified schema namecharnullabletable_nameFully qualified table namecharindexedprimarytable_typeOne of: table, viewcharnullabledescriptionBrief description of the tableunicodeCharnullableutypeutype if the table corresponds to a data modelcharnullabletable_indexSuggested position this table should take in a sorted list of tables from this data centerintnullablesourcerdId of the originating rd (local information)charnullablenrowsThe approximate size of the table in rowslongnullabletap_schema.schemasschema_nameschema_name
tap_schema.columnsColumns in tables available for ADQL querying.table_nameFully qualified table namecharindexedprimarycolumn_nameColumn namecharindexedprimarydescriptionBrief description of columnunicodeCharnullableunitUnit in VO standard formatcharnullableucdUCD of column if anycharnullableutypeUtype of column if anycharnullabledatatypeADQL datatypecharnullablearraysizeArraysize in VOTable notationcharnullablextypeVOTable extended type information (for special interpretation of data content, e.g., timestamps or points)charnullable"size"Legacy length (ignore if you can).intnullableprincipalIs column principal?intindexedIs there an index on this column?intstdIs this a standard column?intsourcerdId of the originating rd (local information)charnullablecolumn_index1-based index of the column in database order.shortnullabletap_schema.tablestable_nametable_name
tap_schema.keysForeign key relationships between tables available for ADQL querying.key_idUnique key identifiercharindexedprimaryfrom_tableFully qualified table namecharnullabletarget_tableFully qualified table namecharnullabledescriptionDescription of this keyunicodeCharnullableutypeUtype of this keycharnullablesourcerdId of the originating rd (local information)charnullabletap_schema.tablesfrom_tabletable_nametap_schema.tablestarget_tabletable_name
tap_schema.key_columnsColumns participating in foreign key relationships between tables
available for ADQL querying.key_idKey identifier from TAP_SCHEMA.keyscharnullablefrom_columnKey column name in the from tablecharnullabletarget_columnKey column in the target tablecharnullablesourcerdId of the originating rd (local information)charnullabletap_schema.keyskey_idkey_id
tap_schema.groupsColumns that are part of groups within tables available for ADQL
querying.table_nameFully qualified table namecharnullablecolumn_nameName of a column belonging to the groupcharnullablecolumn_utypeutype the column within the groupcharnullablegroup_nameName of the groupcharnullablegroup_utypeutype of the groupcharnullablesourcerdId of the originating rd (local information)charnullabletap_schema.tablestable_nametable_name