Magical Database

He also has a file of maps to bad guy labs.

Horatio: I need a report on all the walls ever made ever.

Tech Guy: I'm on it... According to this, this particular model of wall is of an excellent quality. It doesn't creak. Unless... there's a body behind it.

—Slackerz making fun of CSI

A special Applied Phlebotinum used primarily in Police Procedural dramas.

No matter what sort of clue the Crime Scene lab has found (blood, wire, rope, oil, perfume, etc), somebody has manufactured a database designed to search through them all. Not only that, our heroes at the crime lab have purchased a copy of this software, the interface devices to input the data in question and have acquired the expertise to use this software (which has so far never been used in another one of their cases) with 100% accuracy on the first attempt.

It should be noted that some of these "magical databases" actually exist, and are in use by various agencies, though they aren't quite as stunningly accurate or omniscient as the Police Procedural suggests. In real life, "Data Mining" is a time-consuming task that has to be practiced. Does each agency host a different server? Which ones pull from each other? Are all servers identical? Are there delays in updating the databases? Not to mention the curious fact that dastardly villains who were clever enough to evade the police this long, probably know how to avoid leaving much for the police to follow. These are all questions the searcher needs to be aware of, and there is no single database that stores 100% of the information.

A key aspect of this trope is that there must be a pre-existing compendium of all possible samples of whatever is being identified. In Real Life, forensics can indeed match samples of, say, paint or glass not only down to manufacturer but even to a specific batch, but this requires two samples: one sample from evidence, and another sample to compare against. This also means that in real forensics, the implications of this evidence are different; while crime dramas typically use the Magical Database to find a new lead from trace evidence, real forensics usually confirms identity after the police have already gotten a lead (i.e. the police already suspect the glass came from the suspect's house or workplace and can prove it by comparing them, as opposed to identifying where the suspect lives with no prior knowledge just from the glass sample).

Forensics labs also have an out for many of these magical databases, since it's generally believable that they would have a database of common murder weapons or components of weapons.

Magical Databases almost always have a Viewer-Friendly Interface. If it's on paper or supernatural, it's a Great Big Book of Everything.

See Akashic Records for a related but older trope.

Examples of Magical Database include:

Anime and Manga

Inspector Runge from Monster keeps an absurdly expansive encyclopedia on practically everything in his head by constantly making a typing motion and saying that he's just calling up the memories as he needs them, or something along those lines.
The titular character of A Certain Magical Index is quite literally one of these considering the database itself is about magic. It should also be noted that in this series, in Magic at least, knowledge quite literally equals power.( There are some spells and such that aren't chronicled in the 103,000 grimoires that are kept in her mind, most notably ones of angelic (or otherwise non-human) origin.)
Somewhat justified in the Ghost in the Shell: Stand Alone Complex considering the heavily cyber-ized world, although it's averted in that it doesn't work all the time.

Comic Books

Almost every depiction of Batman has this, whether it's his own vast knowledge (a la Sherlock Holmes), the Batcave computer, or a combination of both. In one Justice League of America issue, it is shown that Batman's database of fingerprints looks at the magical databases of the Batcave, the GCPD, AFIS, JLA Headquarters and Superman's fortress of solitude. This allows him to determine the identity of a 31st century superhero because Superman had been friends with him the past... err... future... Oracle has taken on the role of database for the hero community at large. She serves as information retriever and disseminator, as well as offering mission-specific hacking and guidance. In an issue of Gotham Central, which focused on the members of the Major Crimes Unit of the Gotham City Police Department, Renee Montoya was attempting to track down the history of a sniper rifle that had been used in several high-profile assassinations. She is seen accessing numerous government databases, including the FBI and ATF, but none of them can give her any useful information. When she mysteriously gains access to a system named "Oracle", which neither she nor her partner can identify, she is shocked (But happy) when it suddenly gives her the complete history of the gun, including the gun shop where it was sold.
The Flash: Impulse is the only Flash able to permanently remember what he reads at super-speed. Once, he read an entire San Francisco public library. It came in less handy than you'd think.
In The Sandman, Dream has a library of all the books that were never written. Including some famous real-world classics whose authors died before they could finish writing them. It also has the books that you might dream of writing some day. Trippy.
Subverted in Queen and Country - when trying to identify a man on a video being used to blackmail a well-known telecom industrialist, the technicians mention to Crocker that they ran his face through a visual database to match him to someone on file. Crocker asks if that actually worked, and one of the techs says it never does, mentioning that the database always wants to match the subject to the late Queen Mother.

Film

The Bourne Identity
- The US government can identify a German citizen and everything she's done her entire life and her family history within moments from a blurry picture.
In the 2008 film Iron Man, Tony Stark, having been frozen out of his company by villain Obidiah Stane, asks his assistant Pepper Potts to hack into Stark's office computer to retrieve some critical files from the company mainframe. Not very magical until Potts stumbles across a video file of Stark's earlier having been taken hostage by a terrorist group. In the video the terrorists are making their demands in some foreign, Arabic-like language. Potts simply clicks a "Translate" button on the video viewer interface, and the audio is translated into perfect (and appropriately accented) English.
- This increases in Magic when you realize that the only justification for this would be that Stane somehow already had it translated, a process which likely took some time - a believable handwave, given the level of technology Stark surrounds himself with. But, as an earlier scene showed, Stane is fluent in several of the Ten Rings' spoken languages.
Subverted in Mr. and Mrs. Smith: When the eponymous female character commands her subordinates to "search the database!", she gets rebutted with a snarky "For what? John Smith?"

Literature

Sherlock Holmes:
- It might be observed that Holmes kept such databases in his head, being able to identify, for example, varieties of tobacco after examination of the ash (he had "written a monograph" on the subject). He also had a substantial collection of home-made biographies, which were usually spoken aloud by Watson for the reader's benefit. So, despite its modern-tech dressing, this is a pretty old detective-story trope.
- Sherlock's older brother Mycroft actually made a living out of this, being a living database for the British Government.
Lord Peter Wimsey series: Wimsey is a living magical database. He also had a home-made "Who's Who" of the underworld, and once managed to identify the maker of a hat which had had its label removed, purely from the style. (Parker remarks that if he hadn't got the hatter, they'd have tried him on the man's dress suit, similarly de-labelled.)
Discworld series
- Death's library in sometimes functions like a Magical Database, instantly delivering books on very obscure subjects when he requests them, or writing out fresh text if his query doesn't require a long answer (the "some of the sheep" response from The Last Continent).
- Hex does this as well since he is basically a sentient, magical computer. As long as he has his teddy bear he'll find out what you want to know.
The Dresden Files
- The Archive in is a being that holds the knowledge of everything ever written down, ever, in the history of mankind.
- There's also Bob, Harry's knowledge spirit in a skull. Bob doesn't have the extensive knowledge of the Archive, but he is Dresden's go-to guy for magical knowledge, and he instinctively knows the current rules of magic.
The Secret Histories: The Karma Catechist is a living database of every spell, ritual and magical concept conceivable in his universe.

Live Action TV

CSI is the king of the Magical Database. They have demonstrated databases on blood, hair, rope, wire, shoe prints, tire treads, tire rubber compositions, and even clown makeup patterns. There was a Lampshade Hanging in a sixth season episode, in which a character sarcastically suggested searching a database to discover the brand of a hot dog.
- And yes, there actually is a national clown registry to prevent identical makeup.
- Amusingly subverted in one episode where Greg is disappointed to learn that there is no hotdog database and winds up spending his entire year's food budget on various brands of hotdogs in an attempt to find a match to one found in a vic's stomach. (He thought the department would re-imburse him. They didn't.)
- The software/database that allows one to find where a picture in New York was taken by measuring the skyline in comparison to a reference height (while the technique is sound, there is no such software).
- However, one episode shows them using Photosynth.
- In fact, it's when CSI avoids the trope that it can be jarring. A reoccurring scene is the local trace evidence guy naming a compound, and the CSI identifying the compound's common name, and its uses, including the more arcane (say, jeweller grinder lubricant) on the top of their head. Said arcane use are always the key to cracking the case. This gets jarring because there are databases to identify the most common uses of chemicals.
- There actually are multiple shoe-print databases available to police. An episode of Cold Case Files discussed a murder case that was solved, thanks to a partial shoe-print on a piece of glass that matched the shoes of a person in the neighborhood, who was found to be the killer.
- The characters in CSI are also lucky that whatever sample of fabric or metal they find, there is always some unique element or polymer in it which is used by a single company in the world, and is located a short car drive away. Did we forget to mention that the magical database knows the exact 100% correct composition of everything you can buy?
A Magical Database is often an implicit background element of investigations in all the Law and Order series. Although they have used such databases for many of the same types of queries as in CSI, the database query itself is more often carried out off-screen, with a lab analyst mentioning that a fiber found at the crime scene matches a luxury brand of purse that is only sold in only three stores in New York City.
- On Law and Order SVU, they often query some supposed national database implied to consist in all sex crime reports recorded by all local precincts throughout the entire country. They also have Warner, whose mind occasionally acts as a virtual Magical Database.
Star Trek: The franchise must hold the freakin' copyright on the Magical Database cause there are like 1500 of them in the series and movies.
- Data can calculate the probability of a successful saucer section separation at high-warp in mere seconds, even though it's never been attempted before.
- Spock can calculate the equations for time travel and memorize Hamlet in the same movie.
- The holodeck can recreate any setting or fictional story known to Man and several other species. (In one of the books, the holodeck can even replay every Opera performance from 1400 to the year 2356. How they managed to record pre-Renaissance operas ... best not to ask. But there's a reason the Federation Time Police look so harried when we see them -- and it's not just Kirk.)
  - The holodeck could get its own section of this trope.
    - At one point, Picard commands the holodeck to recreate a specific date and time in a Parisian café, complete with accurate interactive portrayals of everyone who was present in the café at the time, in order to relive a memory on a whim. His subsequent disgust at himself for doing so clearly indicates this is not a holodeck program he'd built himself - the data already existed in the computer.
- The Enterprise Main Computer carries all kinds of info like the launch codes to the Voyager probe built over 200 years earlier, or the command codes to every other Federation ship. And yet, when it would actually be useful for the computer to find a piece of obscure information, such as in "The Naked Now" or "Darmok", it takes hours. On the other hand, this matches real database performance - selecting a specific single record is far, far, far faster and easier than a complex query with plenty of cross-referencing, calculations on and parsing of retrieved data, and presumably multiple sources. "Darmok" also contains more than a little Fridge Logic, in that the database actually knew the stories they were talking about, and yet nobody had made the link before.
- One episode of TNG, "The Chase", had an intersection of two of these. The computer needed to do a very complex calculation involving genetic code and the locations of planets in the distant past. It would take several hours, and both the Federation, the Klingons, and the Cardassians agreed to view the results simultaneously. The Klingon commander, in the interim, tried to persuade Data to do so much faster, basically saying that Data is even more powerful than the ship's incredibly powerful computer.
NCIS
- Abby, the forensic scientist, tells us that her ex-boyfriend has made a database of databases after using a magic database of the measures of car fronts.
- A database of turkey DNA comes in to play.
- This trope was lampshaded with:

"Can you believe someone put together a database of grille dimensions?"

- They also regularly catch spies by comparing their facial features to records. As if spies were celebrities sort of like sports stars and opponents would not be at pains to keep the identity of spies obscure and could not disguise facial features in any event.
  - Even sillier, they sometimes call Interpol to ID a spy. As if Interpol would do that. Setting aside the fact that they are a police organization, not an intelligence agency, no government would provide them any information if they did.
Torchwood's main characters are a secret organization with nationwide database records sorted by an ancient alien computer system. The team is capable of literally retconning anything by changing the database.
- Torchwood also subverted it once - just as Jack and Toshiko are getting ready to search every database they have, Owen announces that he's already found the man they're looking for. He was listed in the phone book.
On Angel, Wolfram & Hart has access to several databases which actually are magical. Before Angel's team got access to these they used "Demons, Demons, Demons: The Demon Database".
- Curiously averted, though, in a third-season episode in which Lilah Morgan has to dig through cabinets of files to find information on Angel.
Painkiller Jane: This is almost the entire purpose of Riley's character—to run the computers that have access to these things.
John Doe features a hero that displays ability of knowing everything that can be known about on earth. He's basically a walking and talking magical database.
- Actually, he knows everything about everything except himself.
- It might be more accurate to say that he has the internet in his head. For example, he doesn't know who Jack the Ripper was, but he knows all the theories on the subject.
And similar to John Doe, there's Kyle, from Kyle XY, who didn't know every trivial fact, only things like mathematical formulas. Well, until he spent a single day reading the World Book.
- More literally, it is revealed that Kyle possesses the entire Zzyzx database in his mind.
Blake's 7: Orac, the super computer, who can read any computer with "tarial cells" and is therefore able to find any data the characters can possibly want. Whether he then tells them what he finds out is another story.....
Doctor Who:
- The Doctor is a living Magical Database. For more recent incarnations, there isn't a single episode in the new or old series where he met an alien, visited a planet, or saw a piece of technology he hadn't seen, invented, or met previously. In the new series, when a bunch of alien cops threaten him and Donna in a language not even the mighty TARDIS can translate he easily understands and berates them in the same language. The man is awesome. But then who knows what anybody might know after traveling the universe for a thousand years...
- And then there's CAL, which contains every book ever written in any language, by any species, since the beginning of time. Including lost works. In both hard copy and digital.
- The episode of the new series "Midnight" averts this somewhat. The 10th Doctor had no idea what the enemy was or how to fight it.
- It's worth mentioning that he IS over nine hundred years old, and putting everything we've seen on-screen together would make about one-hundredth of his life.
Spooks - well, maybe it's magic, or maybe MI 5 really can do that stuff...
Chuck is a walking-talking database, able to identify terrorists on sight, however there is also such a database under the Orange Orange used by Sarah and Casey. In "Chuck vs. Santa Claus" we see it pulls up the record of "Ned" who has no criminal record, and is listed as having never been married or divorced. You know how powerful a computer is when it categorizes you by things you haven't done rather than by what you have done. Then again, it is a U.S. government computer...
- It doesn't seem too farfetched since getting married in a legal sense requires a marriage license. And since in the US, being married grants several benefits in things like taxes, martial status is generally a standard appearance on many forms.
Ziggy from Quantum Leap not only apparently has records of the minutiae of decades' worth of the day-to-day activities of pretty much everyone who was alive at the same time as Sam Beckett, but can also calculate the probability that Sam's interference in history will have the desired effect. And regardless of the percentage calculated, Ziggy is always right. Except for a couple episodes where despite an abnormally high percentage, Sam just "knows" he has to do something else. The times when Sam "knows" he has to do something else also are ones where all signs point to Al misleading or outright lying to Sam because of ulterior motives.
- One episode has Hal using Ziggy to help Sam set up an ambush on a man walking around a corner, complete with a precise countdown. Apparently Ziggy has recordings of every human being's movements everywhere ever down to the second.
E-Ring had an example in the episode The General. Said general is kidnapped in Spain. In order to identify his kidnapper, the main character asks to consult the Voice Database of the Spanish Government (which apparently includes voice samples of each of the 40 million citizens of the country and is regularly updated to match voice changes due to aging, disease or plain mood swings), and then uses an experimental, American exclusive application to compare its files with the record of the kidnapper's voice he has. This leads to the obvious question of why on Earth would a government keep a voice database of all its citizens if it had no way of consulting it.
In an episode of Judging Amy, the DNA identifying computer with a database of known criminals returned a result of... cat DNA! Which actually justified. Its not that uncommon to stumble upon Animal DNA (Pets, Strays etc.) on a Crimescene so checking for the right number of chromosomes and some markers makes sense before you go onto a useless orgy of comparing datasets to a nonsensical sample.
Dexter
- An episode had Dexter identifying an STD in some bloodwork, then going into the Florida STD Database to find the names of people afflicted with that particular—and, of course, extremely rare—strain. It is implied that he never leaves the building during all of this, so Dexter's miraculous set of databases even cover what you might be doing with your genitals.
- Subverted with Trinity. His DNA is collected halfway through the season but it can't be used to identify him because he has no criminal record and isn't in the database.
An episode of the Red Dwarf 2009 revival parodies this. After returning to Earth circa 2009, the guys from Red Dwarf find out that they are characters from a TV show by way of a video store showing the currently playing episode on their TVs. One salesman comments he never liked the show, and questions how a device Kryten is holding could know everything. Lister then asks the Kryten who the man is, which Kryten finds out from the device that he is "a pompous know-it-all, with a very small penis."
- It does explain that it learns this by hacking into and reading him emails. Less magic database, more magic scanner.
Castle:
- Although the NYPD police detectives usually make do with a humble whiteboard and footwork, this trope is taken to hilariously ludicrous extremes in the two-parter "Tick...Tick...Tick..." / "Boom!" in which the FBI have smart boards so amazing that they gradually go from matching driver's license photos to witness sketches to being able to pinpoint the exact location of a hostage (down the room she's being held in) thanks to a blurry image of what might be a bridge and the ambient noise of a subway.
- It's memorably subverted in a first season episode, when Beckett says they'll need to look someone up in the missing persons' database- a bunch of paper folders.
- The man from The Men in Black in one episode has a database in a suitcase. It instantly pinpoints a man's location by using his cellphone then automatically finds a Magical Security Camera in the area and maps a small part of the man's face onto a model, extrapolates the rest of his face from that, and pops up with an identity. Castle and Beckett as surprisingly unphased by the technology.
David of Wishbone apparently has access to a database of dog breeds that includes things like their jaw measurements, for some reason. It has a very '90s aesthetic to it, like an over-the-top hacker-movie interface run on an old Macintosh OS.
Alcatraz has a database in their Bat Cave that can find, in seconds, a complete map of all private bomb shelters built in the 1960s by a company that went out of business decades ago.

Radio

The titular book of The Hitchhiker's Guide to the Galaxy may be a subversion of this, as it contains data on almost everything in existence but a good deal of that data is either made up on a whim or wildly inaccurate.

Video Games

ARI in Heavy Rain is connected in some way to the FBI database.
In Grand Theft Auto IV, the criminal dispatching minigame starts by looking up a perp from a stolen cop car's laptop. This gives an exact, updating location of the criminal for you to chase down.
In Kingdom Hearts 2, Sora seems to think that Ansem's computer is one of these. Because the computer belonging to the guy you killed last year will have info on where your friends are right now, right?
Patchouli Knowledge (It's in her name, duh!) of Touhou fame is an effective Human(oid) Magical Database, thanks to her centuries of study and self-made Library of Babel. In Subterranean Animism, she is capable of spilling out the histories and powers of every Youkai Marisa meets in her adventure... with the slight problem of taking until after the yokai was defeated to look up any relevant information.
- She also applied her knowledge to other tasks, such as constructing a spaceship from plywood, duct tape, and a whole lot of Functional Magic.
- To push the point home, the only character who probably trumps her in intelligence might be Eirin Yagokoro, the Brain of the Moon. Very few humans know anything significant about the advanced Lunarian society and their technology (for their own protection, to some extent). In Silent Sinner In Blue, Patchouli not only makes remarkably accurate predictions regarding the timing of their rocket's flight to get to the Lunar Capital but she also immediately identifies the Lunar Veil, a Lunarian device that allows flawless travel between the Earth and Moon, that Eirin had covertly attached to the rocket. The ever-collected Eirin's first thought is stab this person now.
Uplink is a game basically built in databases, it features a Social Security Database, a Criminal Database and an Academic Database which store all the important people in the game and every life you'll ever need to ruin (including yours). And the Inter NIC, a database containing every public website in the world, which is to say a few hundred in the actual game.

Western Animation

From a Western Animation: From Jem episode, "In Search of the Stolen Album" in which Synergy, Jem's super-computer is able to scan clues that "Misfits"'s treasure hunt joke on the Holograms in a matter of moments—and even the reasons behind the places.
Wade from Kim Possible has more or less everything in the database, which of course comes in handy very often. Somewhat justified that he is a highly skilled hacker using Rapid-Fire Typing with his Magical Computer.